Psyc 102

MRI

MRI uses magnetic fields and radio waves to generate pulses of energy within the brain, instead of x-rays (greater clarity and resolution); as pulse is tuned to different frequencies, some atoms line up with the magnetic field. When the magnetic pulse is turned off, the atoms vibrate (resonate) as they return to their original positions; special radio receivers detect this resonance and channel the information to a computer which generates images of the locations of different atom in areas of the brain. It is most useful for providing clear images of anatomical details; PET scans provide better information about function. An MRI can distinguish brain parts as small as one or two millimeters. - fMRI (functional MRI) registers changes in metabolism; activity as it happens; combines some of the benefits of both techniques by detecting magnetic changes in the flow of blood to cells in the brain; allows more precise claims about both structure and function...researchers have begun to use this technology in attention, perception, language processing and memory (Cabeza and Nyberg, 2000). Brain scan video:Daniel was trained in military medicine, then went on to medical imaging, took family member to psychiatrist for being suicidal- family would be shaped by someone who is stable and happy- change generations, SPECT- nuclear medicine- blood flow and activity, how your brain works- normal, over and under, Daniel got into psychiatrists, brain scans of brain behavior, shape matters- healthy is typically in the back, stroke and Alzheimer's creates holes and deterioration- starts in brain 30-50 years before symptoms, TBI, drug abuse, OCD- front part works too hard, epilepsy- increased activity, symptom clusters and talking to people but images should there was another way- psychiatrists typically guessed and did not look at the organ that was effected, depression has different types- brain scans look different- high/low activity in the brain- treatment needs to be individualized, TBI- cause of psychiatric illness, behavior could be expression of the problem, undiagnosed brain problems- suicide, anxiety, homelessness, substance use, understand criminal behavior- often people who do bad things have troubled brains- brains can be rehabilitated- re-evaluate and treat, make them more function so they can be successful after prison, you can change people's brain and when you do you change people's lives- you can make it better, active and retired NFL players brains- put players on a brain smart program- 80% could improve in blood flow, memory and mood- NOT stuck with the brain you have- can reverse brain damage, ADHD, dementia- find home for- intensive brain rehab, 4 years later still knows Husband's name, violent phots and behavior- colorblind, most would have medicated, but SPECT said to look at brain to see what he needed- cyst in left temporal lobe, cyst was removed- behavior went back to normal- sweet, loving, change person's life and generations to come

colour blindness

Dalton is the theorist) There are three forms of colour blindness: Trichromats: can perceive all three primary colours Monochromats: totally colour blind and cannot discriminate among wavelengths Dichromats: can distinguish only two of the three basic colous; difficulty with red/green (2% of men) or blue/yellow. This is inherited; difficulty with the cone pigments; genes are located on the X chromosome

PET

The PET scan tracks radioactive markers injected into the bloodstream to enable researchers to observe metabolic activity by recording glucose use taking place in the brain (cerebral blood flow). One problem is that although they efficiently display cortical function, they lack spatial resolution and precise anatomical localization of the activated region.

Sensations

The elementary components, or building blocks of perception, such as patterns of light and dark, a bitter taste, or a change in temperature. Sensation is the process in which the sense organ receptor cells are stimulated and relay their initial information to higher brain centres for further processing. Sensations- maintain balance, sensations are basic components- see patterns, taste, see, feel, smell, hear

figure-ground relationship

The figure (main object of visual attention) and the ground (background) can be reversed. What do you see on the slide? The Vase or the two faces looking at each other?

Cross-cultural

uMay be interested in characteristics that might be universal but vary from one to another u uMay use ethnography: a descriptive, qualitative technique directed toward understanding a culture or a distinct social group through participant observation [researcher spends time in the community participating in daily life] u uLimitation: assumes that by immersing self in culture you are able to understand beliefs and behaviours Ethnicity is people's common traits, background, and allegiances which are often cultural, religious, or language-based and learned from family, friends and experiences Culture reflects a person's racial and ethnic background, religious and social values, artistic and musical tastes and scholarly interests, etc. Individualistic cultures (more interested in the good of the individual - getting ahead, accomplishments) versus collectivistic cultures (more interested in the good of the group - often individual sacrifice for that good). These types of cultures may make people behave differently in certain areas (e.g., helping behaviours, aggression) Important Fact: for nearly 75 years of research, participants were 18 year old male 1st year students with European backgrounds and the differences with others was not important - then women were added as participants and then older adults and then children - found out these groups do not respond the same way (even within the same background) Ethnocentrism: the tendency to believe that one's own ethnic or cultural group is the standard, the reference point against which other people and groups should be judged - this should be avoided in research (and in life) - leads to an inaccurate way of understanding the world (distortion and prejudice) - people are often unaware of the fact they hold ethnocentric (monocultural) beliefs about their own superiority -there is no genetic basis for race (Black, White, Asian, etc.) - Anyone who has ever travelled has encountered other cultures concept of time...and North Americans/Europeans get very frustrated and agitated when things are not INSTANT...you MUST realize what it is like and then "go with the flow" otherwise it will be you who has the stroke OR NEVER GETS SERVICE OR ENDS UP IN JAIL Class: not as rigid in this culture but still in other cultures Gender: male, female, lesbian, gay, bisexual, transgender, queer, other categories 2SLGBTQ+ Age or disabilities: exceptional/gifted, mental retardation (intellectual disability), learning disabilities, physical disabilities, elderly We should be looking at diversity within groups themselves versus between groups. Between groups often causes negative attitudes, that can lead to prejudice and discrimination.

Structure of the eye

Ø1st step in transduction process lBring the incoming light energy to the light-sensitive receptor cells at the back of each eye Light rays from the outside world first pass through the cornea, a clear curved membrane or 'window'. The cornea bends light so that it is sharply focused within the eye. Abnormalities in the shape of the cornea cause astigmatism. The pupil is the small, round hole in the iris through which light passes. The iris causes the pupil to dilate (enlarge) under dim viewing conditions to let in more light and to contract (shrink) under brightness to let in less light. Next comes the ring-shaped iris, which gives the eye its color. The iris is a muscle that is controlled by the autonomic nervous system. Its function is to regulate the size of the pupil. Behind the pupil, light continues through the lens, another transparent structure whose function is to fine-tune the focusing of the light. The lens brings an image into focus through changing its shape, in a process called accommodation. Specifically, the lens becomes more rounded for focusing on nearby objects and flatter for more distant objects (the cornea, which has a fixed shape, cannot make these adjustments for different distances). With age, the lens loses much of its elasticity and keeps the flatter shape appropriate for viewing at a distance. As a result, many middle-aged people start to need glasses for reading or bifocals with a near-vision portion in the lower part of the glass. If either is too long or too short, blurred image is formed (people with elongated eyeballs are MYOPIC (nearsighted); able to see close to them but a problem with distance - image falls in front of the retina. In HYPEROPIC (farsighted)conditions, people have a shortened eyeball and have trouble seeing up close (image is focused behind the retina). Ability to see clearly depends on the lens' ability to focus the light directly on the retina, hyperopia- lens does not thicken enough so the focal point is behind the retina, as we age, the eyeball typically gets shorter over time, glasses and contacts correct the lens' inability to focus the light properly, playing action video games may improve eyesight but not replace the need for corrective lens Research by Belchior et al. (2013) suggests that playing action video games might also be effective in improving eyesight, even in older adults. The retina is a multi-layered screen of cells that lines the back inside surface of the eyeball. It is one of the most fascinating tissues in the body - both because of its function, which is to transform patterns of light into images that the brain can use, and because of its structure, which illustrates many basic principles of neural organization. In an odd twist of nature, the image projected on the retina is upside down. That is, light from the top part of the visual field stimulates photoreceptor cells in the bottom part of the retina and vice versa.

Structure of the ear

ØAudition (hearing) ØTranslates sound waves into mechanical motion and then into electrical impulses the brain can interpret Ears receive sound and send to the brain to interpret Balance Outer ear, middle ear and inner ear Outer: pinna, ear canal, funnel sounds into inner ear Inner ear turns sounds into vibrations, sounds hit the eardrum and cause it to move, eustachian tube keeps the air pressure balanced on both sides of the eardrum, causes 3 bones (ossicles) vibrate and the vibration is sent to inner ear- changes vibrations into messages to go to the brain (nerve signals), cochlea, vestibule and semicircular canals, cochlea has fluid (wave), moving fluid to transmit signals for balance, signals go from the cochlea through the auditory nerve, signals from semicircular canals go along the vestibular nerve and then to the brain- brain decoded signals to get information

Depth perception

ØDistance from an object and distance between objects Ø ØHeight, weight, depth Ø ØMonocular cues: depth cues that do NOT depend on two eyes Ø ØBinocular cues: depth cues that do depend on two eyes Retina receives information in only two dimensions- length and width and then the brain translates these into three dimensions- height, width and length via monocular and binocular depth cues- all work together at the same time

Gestalt laws of organization

ØLaw of Pragnanz: Gestalt principle that when items or stimuli can be grouped together and seen as a whole, they will be Similarity, proximity, closure and continuity, law of proximity- objects that are near one another are likely to be perceived as part of the same configuration, law of similarity- when parts of a configuration are perceived as similar, they will be perceived as belonging together, lines of white dots and lines of black dots, law of continuity- People link individual elements together so that they form a continuous line or pattern that makes sense, law of closure- people tend to close the open edges of a figure or fill in gaps in an incomplete figure so that their identification of the form is more complete than what is actually there

outer ear

ØPinna (tissue on outside of head) Ø ØEardrum/tympanic membrane(boundary between the outer and middle ear) Ø ØWhen sound waves enter the ear, they produce changes in the pressure of the air on the eardrum, causing eardrum to vibrate

Eye movements

ØSaccades: rapid, voluntary movements of the eyes ØPeople use eye fixations to form representations of visual world ØPerceptual scan: size of the region a person sees when fixating visually people use both central vision (at the fovea) and peripheral vision (at the non-central regions of the eye).

Neuroplasticity

•Ability to change (plasticity) • •During course of development, network of neurons change in four primary ways: • •Growth of dendrites and axons •Synaptogenesis (formation of new synapses) •Pruning (death of certain neurons and retraction of axons to remove connections that aren't useful) •Myelinization (insulation of axons with a myelin sheath) The neurons can have a growth of dendrites and axons (these can branch off in many different directions). Synaptogensis or the formation of new synapses can also occur. A human fetus displays simple synaptic contacts in the fifth gestational month. By the seventh gestational month, synaptic development on the deepest cortical neurons is extensive. After birth, the number of synapses increases rapidly. In the visual cortex, synaptic density almost doubles between ages 2 months and 4 months and then continues to increase until 1 year of age. Pruning Just as sculptors start with a block of stone and chisel the unwanted pieces away, the brain does the same thing with cell death and synaptic pruning. The "chisel" in the brain could be of several forms that include a genetic signal, experience, reproductive hormones, and even stress. How does the brain achieve this elimination of neurons? The simplest explanation is competition, sometimes referred to as neural Darwinism. Charles Darwin believed that one key to evolution is the production of variation in the traits that a species possesses. According to a Darwinian perspective, then, more animals are born than can survive to adulthood, and environmental pressures "weed out" the less-fit ones. Synaptic pruning may also help an individual adapt oto\ Myelinizaton Paul Emil Flechsig was a German neuroanatomist, psychiatrist and neuropathologist. He is mainly remembered today for his research of myelinogenesis. Myelinogenesis is a technique he pioneered in which he studied brains of the late term fetus and newborn by staining for myelin. Between about two months before and after birth, most of the cerebral cortex becomes myelinated. The order in which this happens appears to reflect the evolutionary order of mammals from less to more complex. He derived a map of the cerebral cortex divided not by histology (as Korbinian Brodmann did) but by order of myelination. Flechsig divided the cortical regions into: an early myelinating primitive zone, which includes the motor cortex and the visual, auditory, and somatosensory cortex; a field bordering the primitive zone that myelinates next; a late-myelinating zone, which he called "association". The last area of the human cerebral cortex to myelinate is the Dorsolateral Prefrontal cortex. This region continues to develop in adolescence and adulthood it is related to executive function and working memory. Research now supports this theory that the brain doesn't quit myelinating until approximately the age of 25. .

Neuronal communication: an electrical and chemical language

•Near the end of the axon, it branches out and at the tip of each branch are terminal buttons Neurotransmitters are chemicals released by neurons that affect other neurons; they are produced from materials in the blood (originally derived from foods). Some regulate actions of glands and muscles; some promote sleep or stimulate mental and physical alertness; some affect learning and memory; some affect motivation, emotions, and psychological disorders (e.g., schizophrenia and depression). Neurotransmitters are chemicals that normally reside inside synaptic vesicles in terminal buds (or buttons) of the axon of the presynaptic neuron and when released move across the synaptic space or synaptic cleft and bind to a receptor site on adjacent dendrites of the postsynaptic neuron thus transmitting the impulse to the next neuron. I use the analogy of a boat going from one marina or dock to another marina or dock. The boat crosses the synaptic gap or space and when it reaches the receptors on the other side or the other marina/dock it can only park in certain spaces. It won't fit in all of the spaces; there are specific receptors depending on the size and shape of the boat. As well, if someone is parked in that spot then the boat will not be able to dock. It is similar to different keys fitting in to different locks as well. Only a certain key will open the door. There are medications that may block the receptor site and therefore the neurotransmitter will not be able to "dock" on the next neuron. When a neurotransmitter affects the adjacent neuron, it has accomplished its main mission. The neurotransmitter is then either neutralized by an enzyme, or drifts away, diffusion, or is taken back up into the neuron that released it in a process known as reuptake. Sometimes neurotransmitters EXCITE (cause the next neuron to fire more easily) or INHIBIT (cause the next neuron to fire less easily) A change in the membrane potential of a neuron due to the release of neurotransmitters is called a POSTSYNAPTIC POTENTIAL. Excitatory post synaptic potential (PSP) makes it easier for the cell to fire; inhibitory PSPs make it harder for the cell to fire. Because thousands of neurons may synapse on a single cell, a single neuron can receive both excitatory and inhibitory PSPs at the same time...so it looks at positives and negatives and then fires if it reaches the threshold. At least 70 neurotransmitters have been identified. However, we only talk about the most common ones. Synapse- an area where two neurons come close enough to each other that they are able to send chemical signals from one cell to the other- synaptic cleft is less than 40 nm, presynaptic neuron sends the impulse while the postsynaptic neuron receives the impulse, neurotransmitters into small sacs called vesicles- each one can contain 1000 neurotransmitters, action potential causes the contents to fuse with the presynaptic membrane and release its contents into the synaptic cleft- react with receptors on the postsynaptic neuron- increase or decrease likelihood of action potential, material needs to be cleared from synaptic cleft- some may just leave- diffusion, reuptake- neurotransmitters go back to presynaptic neuron and are recycled and reused, enzymes break down, goes back to presynaptic neuron to make more neurotransmitters

The goals of psychology

a.describing what happens (make accurate observations - data - using an appropriate level of analysis (from the broadest, most global level down to the most minute, specific level), not trying to explain, observation bias (you may not see things that you don't want to see or read in to a situation something that you do want to see but that may not actually be there) b. explaining what happens (goes beyond what is being observed), why? c. predicting what will happen (statements of likelihood something will occur or a given relationship will be found), easier said than done- we do not always behave in rational ways d. controlling what happens (for many control is the central, powerful goal). Control actually means making behavior happen or not happen, depending on what behavior we are looking at. It may mean starting it, stopping, it, maintaining it, and influencing its form, the strength of the behavior or the rate of occurrence

Peripheral nervous system

autonomic nervous system- sympathetic and parasympathetic, sensory-somatic- sensory and motor

William James

often regarded as the father of psychology, once said that psychology was a "nasty little subject" because it is so hard to study and simple explanations are few and far between. Humans are very complicated beings. Our behavior is not as simple as one would think. We do not behave the same way every time we encounter the same situation...there are many reasons why (could be our mood, could be our "day", could be the weather, could be who we are with, etc.) uWilliam James (1842-1910) believed that the study of consciousness was an ongoing stream, a property of mind in continuous interaction with the environment u uWrote "The Principles of Psychology"

The scientific method

uA set of procedures for gathering and interpreting evidence in ways that help ensure that psychological research generates valid, reliable conclusions by minimizing sources of error u uPsychology is considered a science to the extent that it follows the scientific method to minimize subjectivity BUT IS IT REALLY A SCIENCE? u1. Identify the problem u2. Conduct background research u3. Formulate a hypothesis u4. Test the hypothesis u5. Analyze the data u6. Interpret the data u7 Publish the results u8. Retest

How is psychology developed

uthe dual roots of psychology are philosophy and physiology uphilosophy (ideas about how knowledge can be acquired) and natural science (particularly physiology - progress in understanding the nervous system, senses, etc.) From philosophy came: empiricism (the view that knowledge can be gathered through careful observation, experimentation or measurement)and rationalism (the view that knowledge can be gained through logic and careful reasoning)

perceiving form: constancy

Size constancy: ability of the perceptual system to recognize that an object remains constant in size regardless of its distance from the observer or the size of its image on the retina; three variables - experience with the true size of the objects (if you have never seen an object "in real life" it is harder to visualize it) - distance between the object and the person (things seem much smaller when they are farther away from you; therefore if you have never been up close to something you may think it is smaller than it actually is) - presence of surrounding objects (often things on social media are placed beside other common items in order to gauge the size of the non-common object - the new Murderous Hornets were placed on someone's finger for comparison to size) When closed door swings open, it creates a different image on the retina but we still know it is a door- perceptual hypothesis remains the same, otherwise we would have to rediscover what something is under different conditions, different flavours, able to recognize tunes, vision- shape constancy allows us to recognize people and objects from many different angles, at a movie screen- eyes adjust to make the screen look normal, brightness constancy- relative brightness of objects looks the same under different conditions of illumination (sun and shade), occurs because the ratio of light intensity between the object and its surroundings are usually constant, the actual brightness of light doesn't matter, size constancy is the perception that the size of objects remains relatively constant even though images on our retina change in size variations and distance, size says the same shape constancy: ØAbility to recognize a shape despite changes in the angle or position from which it is viewed

Inattentional blindness

is the inability to detect unexpected objects. Research shows that unless you pay attention you can miss even the most conspicuous events around you (e.g., a pilot may not notice an unanticipated plane, you are playing a video game and not notice someone coming into the room). It is important to remember that we can only do so much at one time.

The science of Psychology

three basic principles are the core of what makes psychology a science A. objectivity (evaluating research and theory on their merits, without preconceived ideas) B. accuracy (base thinking on detailed and thorough study that is as precise as possible) C. healthy skepticism (a cautious view of data, hypotheses, and theories until results are repeated, verified, and established over time Standardization means asking the same questions in the same way and scoring the responses according to pre-established rules. We will discuss some other ways of ensuring this shortly. We must use systematic observation and not subjective, and research must be replicable...others need to be able to find the same results.

Control procedures

uSingle-blind control: participant does not know to which condition he or she is assigned (experimental or control) uDouble-blind control: both the participant and the researcher administering the treatment are unaware of the experimental condition to which the participant is assigned uPlacebo control: human participants believe that they are receiving a treatment that may be effective, but in which they are actually receiving a treatment that is known not to be effective Researchers put controls in place in order to attempt to hold constant all potential confounding variables and conditions. There are many ways to do this. Because of the placebo effect and the expectancy effect it is good that the participants (and sometimes the researcher) are not aware of who is in the experimental group and who is in the control group.

EEG

A record of electrical brain wave patterns obtained through electrodes placed on the scalp; it can be used to study the relationship between psychological activities and brain response. Although the EEG is a rather gross measure that taps the electrical activity of thousands of neurons in many parts of the brain, specific EEG patterns correspond to certain states of consciousness, such as wakefulness and sleep. Clinicians also use the EEG to detect abnormal electrical patterns that signal the presence of brain disorders. Researchers are especially interested in changes in the EEG record that accompany specific psychological events, such as presentation of a sensory stimulus. Change in the EEG that accompany such events are called event-related potentials (ERPSs).

Neuroscience and biopsychology

Neuroscience is an interdisciplinary field studying how biological processes relate to both behavioural and mental processes. Neuroscientists concern themselves with all aspects of the nervous system - its anatomy, chemistry, physiology, development, and functioning. And Biopsychology is the scientific study of the biology of behaviour and mental processes, usually in animals however some do study humans as well using noninvasive physiological research methods.

Endocrine system

It is the 2nd communication system after the neuronal communication system. Throughout each day, glands manufacture and secrete substances that affect many of our behaviours. It contains ductless glands that secrete hormones directly into the bloodstream (rather than through a specific duct into a target organ); hormones are chemicals that travel through the bloodstream to target organs. The Endocrine System is very vital at certain stages of life and in certain situations. Hormones influence body growth (initiate, maintain and stop development of primary and secondary sexual characteristics); influence levels of arousal and awareness; serve as the basis for mood changes; and regulate metabolism. It promotes the survival of the organism by helping fight infections and disease. Endocrine glands respond to the levels of chemicals in the bloodstream or are stimulated by other hormones or by nerve impulses from the brain; hormones are then secreted into the blood and travel to distant target cells that have specific receptors by exerting influence on the body's program of chemical regulation only at the places that are genetically predetermined to respond to them The hypothalamus serves a relay station between the endocrine system and the CNS; specialized cells in the hypothalamus receive messages from other brain cells, commanding it to release a number of different hormones to the pituitary gland where they either stimulate or inhibit the release of other hormones. The pituitary gland is often called the "master gland" because it produces about 10 different kinds of hormones that influence the secretions of all the other endocrine glands, as well as hormone that regulates growth. In men, it stimulates production of testosterone (production of sperm) and is also involved in development of male secondary sexual characteristics (facial and body hair, voice change and physical maturation). In women, it stimulates the production of estrogen, which is essential to the hormonal chain reaction that triggers the release of ova from the woman's ovaries, making her fertile. Certain birth control pills work by blocking the mechanism in the pituitary gland that controls this hormone flow, thus preventing the ova from being released. The thyroid is responsible for metabolism -( hyperthyroidism and hypothyroidism); it secretes thyroxin. The adrenal glands above the kidneys regulate Blood Pressure; the kidneys also release cortisol in response to stress (these are not good for you and can cause damage to internal organs). The pancreatic hormone insulin regulates blood sugars.

Perception

Perception: the process whereby an organism selects and interprets sensory input to give it meaning (e.g., when light strikes the eyeball...it initiates electrochemical changes and you experience the sensation as light). However, your interpretation of the pattern of light and its resulting neural representation as a specific image are part of perception. Sensation to Perception - the process Sensation 1. Stimulus is received by sensory receptors 2. Receptors translate stimulus properties into nerve impulses (transduction) 3. Feature detectors analyze stimulus features 4. Stimulus features are reconstructed into neural representation 5. Neural representation is compared with previously stored information in brain 6. Marching process results in recognition and interpretation of stimuli Perception: everyone perceives things differently- heat, different scents- do not argue with others- everyone else's is valid, brightness of light is perceived- light eyes= bright light too intense

The great debates of psychology

The Nature-Nurture Debate poses the following question "Are our behaviours attributable mostly to our genes (nature) or to our rearing environments (nurture)? The biological perspective is nature; the behaviourist perspective is nurture. It is especially controversial in the areas of intelligence, personality, and psychopathology. John Locke thought us to be blank slates or "tabula rasa" and likened the human mind to be like a blank piece of paper that hadn't been written on yet. Today, just about everyone believes that it is an interaction between the two. The Free Will-Determinism Debate poses the following question "To what extent are our behaviours freely selected rather than caused by factors outside of our control?" We like to assume that we do have choice and control over our behaviours; others, however, believe that free will is an illusion. Mind-Body Dualism Debate: many early philosophers held a position of mind-body dualism, the belief that the mind is a spiritual entity not subject to physical laws that govern the body. Others, however, question, that if the mind is not composed of physical matter, how could it become aware of bodily sensations, and how could its thoughts exert control over bodily functions? French philosopher Rene Descartes believe that the two interact through the brain's pineal gland. In contrast monism holds that the mind and body are one and not separate; it helped set the stage for psychology, along with British empiricism (observation is the most valid approach to knowledge).

B.F. Skinner

udiffered from Watson by adding reinforcement (reward his subjects for behaving the way he wanted them to) and punishment u uReinforcement increases the likelihood a behaviour will be repeated; punishmentdecreases the likelihood a behaviour will be repeated (both positive - something added - and negative - something taken away) B.F. Skinner was another influential Behaviourist. He also argued that principles derived from animal research applied to humans. Reinforcement and punishment will be discussed in more detail in the chapter on Learning. Behaviouristprinciples have yielded more humane approaches to the education of children and to the treatment of behavior disorders through the use of positive reinforcement (giving a reward for good behavior), a much more effective tool in learning than punishment (especially harsh punishment).

Monitoring neural activity

•Single-unit recording •insert a thin wire, needle, or glass tube containing an electrolyte solution into or next to a single neuron to measure its electrical activity (usually animals)

Parietal lobe

•integrating visual input and monitoring the body's position in space • •somatosensory cortex registers information from the skin senses (touch, temperature, pain) (figure 3.11, page 102 of textbook) • •Melzack (McGill U) "phantom limb" • •damage differs depending on whether damage is left or right hemisphere • •damage to left tends to produce aphasias: (language disorders) or agnosias:(inability to perceive objects) • •damage to right lobe causes individual to neglect the left side of his body (e.g., failure to dress that side) The phenomenon of a phantom limb is a common experience after a limb has been amputated or its sensory roots have been destroyed. A complete break of the spinal cord also often leads to a phantom body below the level of the break. Furthermore, a phantom of the breast, the penis, or of other innervated body parts is reported after surgical removal of the structure. A substantial number of children who are born without a limb feel a phantom of the missing part, suggesting that the neural network, or 'neuromatrix', that subserves body sensation has a genetically determined substrate that is modified by sensory experience.

Temporal lobe

•left contains a language comprehension centre (Wernicke's area) and is connected to Broca's area • •memory function and social understanding • •contains auditory cortex • •damage: memory loss, altered emotional responding, language difficulties It was named for Carl Wernicke who discovered in 1874 that damage to this cortical region left patients unable to understand written or spoken speech. There is also a memory function and social understanding. The temporal lobe contains the auditory (hearing) cortex. Damage to this area can result in memory loss, altered emotional responding, and language difficulties.

Occipital lobe

•processes visual input •primary visual cortex receives sensory input directly from the eyes •parietal and occipital in concert for hand-eye coordination

Action potential

•neural impulse that carries information along the axon of a neuron •generated when positively charged ions move in and out through channels in the axon's membrane •"all or none law" (either there is or there isn't - no "partial" action potential) •After neuron fires, there is a brief refactory period where it cannot fire again (repolarizes) The Electrical Activity of Neurons Neurons do two important things: generate electricity and release chemicals that allow them to communicate with other neurons and with muscles and glands. Let's first consider how they generate electricity - how the nerve impulses occur. Nerve activation involves three basic steps: 1.At rest, the neuron has an electrical resting potential due to the distribution of positively an negatively charged chemicals (ions) inside and outside the neuron 2.When stimulated, a flow of ions in and out through the cell membrane reverses the electrical charge of the resting potential producing an action potential , or nerve impulse. 3.The original distribution of ions is restored, and the neuron is again at rest and capable of again being activated. The action potential is the neural impulse that carries information along the axon of a neuron; it cannot be produced beneath the myelin sheath. It is generated when positively charged ions move in and out through channels in the axon's membrane (sodium and potassium). It follows an "all or none law" (either there is or there isn't one - there is no "partial" action potential) After the neuron fires, there is a brief refactory period where it cannot fire again (repolarizes). Action potential- momentary reversal of the membrane potential, basis for electrical stimulation, -70, depolarization- makes the cell less positive- move closer to 0, threshold is reached- generally around -55- sodium channels open so sodium goes into the cell, rising phase- gets closer to 0, influx of positive ions= action potential, peak- sodium closes and potassium channels open to let potassium out, repolarization (falling phase) and then hyperpolarization- refractory periods- difficult to stimulate an impulse, then resting potential and can be restimulated . In a resting state, the neuron's sodium and potassium channels are closed, and the concentration of Na+ ions is 10 times higher outside the neuron than inside it. But when a neuron is stimulated sufficiently, sodium channels open. Attracted by the negative protein ions inside, positively charged sodium ions flood into the axon, creating a state of depolarization (remember, when it comes to electrical charges, opposites attract). In an instant, the interior now becomes positive in relation to the outside, resting the action potential. In a reflex action to restore the resting state, the cell closes its sodium channels, and positively charged potassium ions flow out through their channels, restoring the negative resting potential. Eventually, the excess sodium ions flow out of the neuron, and the escaped potassium ions are recovered. Once an action potential occurs at any point on the membrane, its effects spread to adjacent sodium channels and the action potential flows down the length of the axon to the axon terminals, like a row of dominoes. Immediately after an impulse passes a point along the axon, however, there is a recover period as the original distribution of ions is re-established. During this absolute refractory period, the membrane is not excitable and cannot generate another action potential. This places an upper limit on the rate at which nerve impulses can occur. In humans, the limit is about 300 impulses per second. It also means that once an action potential starts, it travels I only one direct, from soma along the axon to the axon terminals. Resting potential - electrical change difference across the neuronal membrane when the neuron is not being stimulated or inhibited, hence it is resting Threshold - membrane potential that is necessary to trigger an action potential Absolute refactory period - the time during which another action potential is impossible; this limits the maximal firing rate. When the action potential reaches the axon terminal buttons, it stimulates the release of neurotransmitter molecules into the synaptic gap (the space between one neuron and the dendrites of another neuron). Terminal buds or buttons Most axons divide and branch many times; at the ends of the "twigs" are found little knobs called terminal buttons or terminal buds. These have a very special function. When the action potential reaches the axon terminal, it stimulates the release of neurotransmitter molecules into the synaptic gap. An individual neuron receives information from the terminal buttons of axons of other neurons - and the terminal bud of its axons form synapses with other neurons. A neuron may receive information from dozens or even hundreds of other neurons.

Ethics in lifespan research

-rules of proper and acceptable conduct when conducting psychological research that includes the treatment of animals and humans, the rights of human beings, and the responsibilities of the investigators - -Respect for the dignity of all persons is the overarching ethical code; its role in all of the others is obvious. -Protection from harm: You cannot (and will not get passed the Research Ethics Board if you are going to cause significant psychological and/or physical harm to either animals or humans. In drug trials, the positives have to outweigh the negatives (the probably benefit is proportionately greater than the risk). -Informed consent: All participants must learn about the study and then agree to participate. Unfortunately, there are often vulnerable populations (audio recording). -Privacy and Confidentiality: all data must be kept separate from any identifying information of the participant (e.g., if the participants are signing a consent form these must be stored separately from any data collected; as well no names are associated with the data and the participants are just #1, #2, etc.) It is also imperative to not discuss or disclose whether someone has participated in a study; if the participant wants to tell others about it, then that is their choice and doesn't violate confidentiality. Often students will ask each other if they participated in a certain study; some may answer "no" even if they have as they want it confidential. -Knowledge of results: all participants are welcome to request the results; however the results will be of the overall study and not that particular participant's results. Those you cannot get. Now, when I did my Master's Thesis, I did get special permission to let my participants see their results as I was measuring brain waves, etc. and the participants were very interested to see their data. The REB agreed that they could if they wanted to (but no one else could see their data - only them). -Deception and debriefing: I will discuss this with vulnerable populations as well (audio recording) -Beneficial treatments (audio recording) -vulnerable populations- informed consent- understand and agree to what is happening, children, elderly, any intellectual disability - need guardian permission, over the age of 7- children can decide for themselves- permission from them- others may volunteer for them and they may not want to, ensure that people with intellectual disability actually understand what is happening

Damage to the visual system

Agnosia: people with agnosia have normal, intact perceptual systems for detecting colours, shapes and motion, and have no verbal, memory or intellectual impairment yet they are unable to recognize things they should be able to. This usually occurs because of injury to the brain from an accident or stroke. These individuals can see the stimuli but cannot name them (e.g., cup, hat). Some visual agnosias are colour or movement or object. Agnosia- deficient in perception, can tell us shape and colour of an object but cannot recognize or name it, Oliver Sax, the man who mistook his wife as a hat book Prosopagnosia - people with this can identify all objects, scenes, places but not faces (recognizing people by their facial features); they know the image is a face but they don't know whose face it is. There are special brain regions "face detectors" - research says YES. Some individual cells around the temporal lobes and some specific to frontal view and side view (ont one neuron....one face). Usually patients with agnosia have lesions or damage to a specific part of the brain - facial recognition is more holistic. Face blindness, cognitive disorder in face perception in which the ability to recognize faces (own face) is impaired, other aspects are fine, development or congenital- lifelong, from childhood, not from TBI but there may be a genetic cause

Mary Whiton Calkins

An interesting side note is that one of William James' Ph.D. students was Mary Whiton Calkins (1863 to 1930) who became the first female president of the American Psychological Association in 1905. Despite being an outstanding student at Harvard, the faculty denied her tenure because she was a woman. She made significant contributions to the study of memory, sensation and self-concept

Basal Ganglia and corpus callosum

Basal Ganglia This is a series of nuclei that control movements and posture (associated with Parkinson's Disease). Parts influence muscle tone and initiate commands to the cerebellum and to higher brain centres. Damage can cause severe behavioural consequences. Corpus Callosum The corpus callosum is a thick band of 200 million or so nerve fibres. It connects the two hemispheres of the brain and there are many connections between the two sides. Damage can result in two separate brains if the corpus callosum is severed (most often because of uncontrollable epilepsy). Basal Ganglia- 5-6 structures surrounding developing thalamus, voluntary motor control- initiation, Parkinson's -neurons that supply dopamine to basal ganglia die- does not function properly and are unable to control voluntary movement- lower dopamine- jerky becomes slow movements then only with assistance of initiating movement- complete paralysis- cannot move when they want to

Binocular cues

Binocular cue #1: binocular disparity: because our two eyes are offset, they produce two different images; our brains use the disparity between these images to calculate depth, with larger disparities meaning closer objects- brain puts everything together, thumb out in front of you- open and close each eye and thumb kind of bounces back and forth, when thumb is close, thumb jumps around a lot Binocular cue #2: binocular convergence- looking at closer objects causes our eyes to converge; our brains use this information to calculate depth, with more convergence meaning closer objects, thumb in really close- pressure in eyes and they have to go cross eyed Retinal disparity: slight difference between the visual images projected on the two retinas This is due to the physical distance from each other (whichever eye is closer will see a slightly different image) and the closer the object the more retinal disparity. Convergence is the movement of the eyes toward the nose and each other in order to keep visual inputs at corresponding points on the retinas as an object moves closer to the observer. As the object gets closer, people will experience "crossed eyes". My mother always told us to stop doing that in case our eyes "stayed that way". Binocular depth cues- most dramatic perception of depth, magic eye photos, 3D movies, feature detects are tuned to depth- respond to stimuli either behind or in front of the point we are fixing our gaze upon, convergence- feel the muscles that are required to turn the eyes inward

The nervous system

CNS distinguishes us from other creatures PNS- all the neuronal structures that lie outside the brain and the spinal cord, neurons carry out the input and output functions that are necessary for us to sense what is going on inside and outside our body and to respond with our muscles and glands The nervous system is composed of billions of highly specialized nerve cells (neurons) that constitute the brain and the nerve fibres found throughout the body. It is subdivided into two major divisions - the peripheral nervous system and the CNS (central nervous system). The CNS consists of all the neurons in the brain and the spinal cord; the PNS is made up of all the neurons forming the nerve fibres that connect the CNS to the body. The job of the CNS is to integrate and coordinate all bodily functions, process all incoming neural messages and send out commands to different parts of the body. The messages both ways go through the spinal cord in a "trunk line" that is housed in a hollow portion of the vertebral column (spinal column); the spinal nerves branch out from the spinal cord between each pair of vertebrae, eventually connecting with muscles and glands. The spinal cord coordinates the activity of the left and right sides of the body and is responsible for simple, fast-action reflexes that do not involve the brain. Damage to the nerves of the spinal cord can result in paralysis of the legs or trunk, as seen in paraplegic individuals (the extent of paralysis depends on how high up the spinal cord the damage occurred; high damage produces greater paralysis. The CNS is isolated from any direct contact with the outside world. The Peripheral Nervous System The role of the PNS is to provide the CNS with information from sensory receptors such as those found in the eyes and ears, and to relay commands from the brain to the body's organs and muscles; the PNS is actually composed of two sets of nerve fibres. Central- brain (cerebrum, cerebral hemispheres- L/R, brainstem- connects brain to spinal cord, midbrain, pons, medulla, cerebellum- development- forebrain (cerebrum), midbrain (midbrain), hindbrain (pons, medulla, cerebellum), and spinal cord, center of the body Peripheral- go out all over the body, nerves- long stringy structures all over the body, carry the axons, ganglia- lumps that are attached to nerves, may contain somas, may bring information in (afferent), axons can carry information away to the periphery (efferent), cranial nerves exit the skull/brain, 12 pairs, spinal nerves come out of spinal cord and pass through the spine, paired on both sides of the body- 31 pairs , root in the front and the back- ganglia, afferent then travel though spinal nerve routes in the back, efferent in the front- mixed nerves, nerves branch repeatedly into tinier and tinier branches, proximal- big nerves that we can see with the naked eye then goes to microscopic in the distal part

Selective attention

Can you study and listen to quiet music??? (did it interrupt you?) Broadbent 1958 uncovered the "cocktail party" phenomenon - a person can hear his or her name spoken across a crowded and noisy room - can't discern the content but can hear the name) - how do people selectively attend? filter theory: states that human beings possess a limited capacity to process information and that perceptual "filters" screen out extraneous information attenuation theory: states that all information is analyzed but that intervening factors inhibit (attenuate) attention so that only selected information reaches the highest centres of processing (research favours this one) People must select among available stimuli (you can drive and listen to the radio) BUT NOT concentrate equally on information from many channels for several tasks simultaneously - e.g., sing to radio, study and identify an odour at the same time Constantly receiving input from all of our senses- to prevent becoming bewildered we use selective attention, reticular activating system and the forebrain- activate cerebral cortex (frontal cortex during selective attention), filter- pay attention to important stimuli and ignore others- attention problems have a hard time not paying attention to everything all at once, filter about what will and will not receive our attention is complex, even if "off"- ready to spring into action if it determines something significant

theories of colour vision

Colour coding - ability to discriminate among colours on the basis of differences in wavelengths Trichromatic Theory: Young-Helmholtz Theory (the two researchers) There are three colours - red, blue and green....from these you can make all colours. There are three types of cones that are especially likely to respond to red, green and blue; however, this does not account for why some colours look more vibrant when placed next to other colours (colour contrast) and does not explain colour blindness (inability to perceive different hues). I have a very hard time distinguishing black from dark navy blue (and recently dark forest green). 1800- any colour in the visible spectrum can be produced by some combination of colours in the wavelength that corresponds with red, green and blue, Trichromatic theory- Thomas Young (English physicist) and Herman VonHellmould (German physiologist), individual cones are most likely to be the most sensitive to red, green or blue, send signals to the brain based on how much they are activated by different lights energy wavelength, visual system then combine signals to recreate the original hue, problems- yellow is produced by activity of red and green receptors, yet some people with red-green colour blindness are able to experience yellow, colour after image- image in a different colour appears after a colour stimulus has been viewed for a while and then withdrawn Opponent-Process Theory (Hering - the researcher) At the level of the retinal ganglion cell, the sensory input from three cone types is translated into an opponent colour system with red opposing green, blue opposing yellow, and white opposing black. Three pairs of mechanism respond to light intensity and wavelengths in different ways. This theory also explains afterimages (stare at a green dot and the afterimage will be red). 1870, three types of cones, but each type responds to different wavelengths, one responds to red OR green, another responds to blue OR yellow, and a third to black OR white, chemical reaction to respond to either stimulus

Colour vision

Colour depends on the wavelengths of the visible light that stimulates the photo receptors; it is not actually physical but is psychological. Therefore, others may perceive colours differently than you do; don't bother to argue whether something is red or orange as we see things differently. There are three important physical dimensions: hue (colour)...objects themselves do not possess colour...colour is a psychological occurrence...how our eyes and brain interpret the wavelengths; brightness (how light or dark the hue appears). This is affected by three variables: greater the intensity of reflected light, the brighter longer the wavelength, less brighter object nearer the wavelengths are to 500-600, the more sensitive the photoreceptors (e.g., school buses are yellow or 580...easily detected) c. the saturation or purity.

CT

Computer-assisted x-ray images are produced in three dimensions (photographic slices); tumours or regions destroyed by strokes, accidents, or other brain abnormalities are picked up in this method. Developed in the 1970s,CT scans take pictures of narrow slices of the brain.A computer analyzes the slices and creates pictures of the brain's interior from many different angles.Pinpointing where injuries or deterioration have occurred helps to clarify relations between brain damage and psychological functioning.CT scans are 100 ties ore sensitive than standard x=ray procedures, and the technological advance was so dramatic that its developers

Autonomic nervous system

Controls involuntary basic life functions, such as heartbeat, digestion, pupil dilation, breathing If we had to consciously think about doing these we would not have time for much else. The ANS must work even when you are asleep; it sustains life processes during anesthesia and prolonged coma states. The ANS deals with survival matters of two kinds: those involving threats to the organism and those involving bodily maintenance; to do this the autonomic nervous system is further divided into the sympathetic nervous system and the parasympathetic nervous system. Controls glands, smooth/involuntary muscle around heart, blood vessels, lining of stomach and intestines, involuntary functions, motivation, emotional behavior and stress responses, sympathetic and parasympathetic- affect same organ or gland in opposing ways The Sympathetic Division governs responses to emergency situations; "fight-or-flight" response (digestion stops, blood flows away from internal organs to the muscles, oxygen transfer increases, heart rate increases)....then when danger is over the parasympathetic system takes over and the individual calms down...digestion resumes, breathing slows down, heart rate slows down. . Arousal function, acts as total unit, stressful situations, increases heart rate, dilates pupils, slows down digestive system, increased RR, mobilizes body to confront stressor The Parasympathetic Division monitors the routine operation of the body's internal functions - carries out the housekeeping duties (elimination of body wastes, protection of visual system - tears and pupil constriction), long-term conservation of body energy. . More specific in actions, one or a few organs at a time, slows down body processes, return to rest- slows down HR, maintain equilibrium- homeostasis with both systems, some acts require both- male sexual response The Sympathetic Nervous System and the Parasympathetic Nervous System cannot both be operational at the same time. This is important to note and crucial when dealing with people with anxiety, etc. To get out of the Sympathetic you must activate the parasympathetic.

Ethics in research

Ethics are in every topic Ethics: a set of moral principles used by researchers to describe how participants in research should be treated. This applies to all stages of the research: participant selection, how the study is carried out, how the data is collected and analyzed, how the results are reported Until WW2- no guidelines for research, assumed that participants were protected from harm- horrifying experiments- Nuremberg Trials- Code- guidelines that outlines the ethics that is needed for research Confidentiality- participants have the right to privacy, any details of their involvement in a study must be kept confidential unless written consent is given Voluntary participation- the researcher must try to ensure that participants consent to be involved in research voluntary, participants must not be pressured in any way or suffer any negative consequences if they choose not to participate Right to withdraw- prior to the study being conducted, participants must be told what the research is about and that they are free to withdraw from the study at any time, the participant should not suffer any negative effects because of this, if a participant is harmed in any way throughout a study, the researcher must withdraw a participant themselves Informed consent procedures- wherever possible, participants should be appropriately informed of the type of study and the reasons for the research before it is conducted and before participants agree to participate, this must be documented, participants must be made aware of any effects or consequences the study may cause them, for participants that are legally incapable, the researcher must provide an appropriate explanation and obtain consent from their guardian, researchers need to be aware of vulnerable groups and ensure they are not abusing their position of power when gaining consent- deception: when a single-blind procedure is needed for the study, researchers must ensure that participants suffer no negative consequences from the research procedures, it also has to be justified by its potential benefits to the community, no other way of achieving the aims of the study, in all cases involving deception, the participants must be debriefed at the conclusion of the study- debriefing- participants are informed of the purpose of the research at the conclusion of the study, the researcher must also correct any beliefs or attitudes the participants may have about the research, includes info, procedures, results and conclusions Accurate reporting- a researcher must report all data accurately, even if they are not happy with the results Professional conduct- at all times throughout the study, researchers are expected to conduct themselves in a professional manner

The brain

Five Principles Governing Brain Organization •Each system involves several brain regions that carry out different types of information processing •There are identifiable pathways that project from one area to the next •Each part of the brain projects to the next in an orderly fashion, resulting in topographically organized regions that can be mapped spatially •the brain is hierarchically organized •the brain systems are organized so that one side of the brain controls the other side of the body This cross-circuit principle, however, has two exceptions; these are olfactory and somatic systems. Olfactory information does not cross but rather projects directly into the same (ipsilateral) side of the brain. Also, the cranial and peripheral nerves do not cross but are connected ipsilaterally (the same side of the brain).This is the part of the CNS that regulates, monitors, processes, and guides the nervous system activity; it is located in the skull and it weighs approximately 3 lbs (1.4 kg). It has two large cerebral hemispheres (right and left), joined by corpus callosum (joins the two halves and permits for transfer of information between the two halves). Lateralization refers to the relatively greater localization of a function in one hemisphere or the other. Corpus callosum- broad, white band of myelinated nerve fibers, neuronal bridge- acts as major communicator between the two hemispheres and allows them to function as a single unit

Illusions

Illusions are perceptions of a physical stimulus that differs from measurable reality and the normal expectations about its appearance (misperception of stimulation). Advertisers use illusions all the time in order to have the "purchaser" focus on whatever it is the advertiser wants you to focus on. Designers do the same (e.g., if you want a room to appear larger and the walls seem higher, paint the walls and ceiling the same colour; if you want smaller make them different). The size is the size, it just appears different. Compelling but incorrect perceptions, erroneous perceptual hypotheses about the nature of the stimuli, intriguing and delightful visual experiences but they also provide important information about how our perceptual processes work under normal conditions. Illusions activate the same brain regions as actual objects or perceptions, typically are attributed to constancies that ordinarily help us to perceive more accurately- size constant relies on distance cues, but distance cues can sometimes fool us Muller-lyon illusion, ponzu illusion- Anyone who is an artist knows about this one....those "disappearing" train tracks, zoner illusion, Wundt illusion, Poggendort illusion-Does the line go straight through the green rectangle or is it crooked? moon illusion- Full moons can look huge when rising, and then when the moon is above the horizon it looks like it has shrunk, image cast on the retina is the same in both cases- false perception caused by cues that ordinarily maintain size constancy- apparent distance, we use trees and buildings to estimate its distance, objects look further away when viewed through filled spaces- 2.5-4x further away, may appear larger because it appears closer, individual differences, reversing staircase illusion- Which way do you see the staircase? Look at it long enough and see if it reverses for you.

John B. Watson

Known as the "father" of Behaviourism uUsed classical conditioning to change "Little Albert's behavior u"Little Albert" experiment Little Albert Experiment- classical conditioning- unconditioned stimulus to create unconditioned response- dog Baby was born to nurse, Albert was raised in a hospital environment and developed normally Gave objects to Albert that he was not afraid of and liked- fires, a monkey, a dog, a rabbit, and a white rat, Loud bar was struck every time Albert reached for the rat- startled, reached again and then heard it and cried, rabbit- cried immediately and moved away from it, then a dog- did not cry- cautious, only cried and tried to get away when dog was up close , then sealed fur coat- albert turned away and was agitated, then Santa mask- more negative response-- Albert became afraid of familiar objects that had the same characteristics as the white rat- generalization, wanted to test if it carried over to other settings, same objects did not show symptoms of withdrawal until it was paired with a loud noise, wanted to see if fear could continue over period of time, Albert went home, tested again with objects and noises- strong withdrawal, phobias are conditioned responses

Monocular depth cues

Monocular depth cue #1: relative size- all else being equal, more distant objects look smaller, things must be further out because they take up less space on our visual field Monocular depth cue #2: texture gradient- object textures become less apparent farther away, colours do not blend together- distinct boundaries close Monocular depth cue #3: interposition- if object A is blocking our view of object B, this must mean that object A is closer to use than object B; also known as occlusion Monocular depth cue #4: linear perspective- parallel lines converge as distance increases, eventually meeting at a vanishing point, railroad tracks in the distance, vanishing point- it does not look parallel anymore, distance between lines is very close together when close to you Monocular depth cue #5: height in plane- distance objects tend to appear higher than closer objects Monocular depth cue #6: light and shadow- objects cast shadows that tell us their three-dimensional shape ØDynamic and static Ø Ø1. motion parallax - when a moving observer stares at a fixed point, the objects behind the point appear to move in the same direction and objects in front of the point appear to move in the opposite direction Ø Ø2. kinetic depth effect: objects that look flat when they are stationary appear three-dimensional when set in motion (e.g., a paper clip) Ø Ø3. linear perspective - based on the principle that distant objects appear to be closer together than nearer objects . interposition: when one object blocks part of another, the first appears to be closer Ø5. texture - little texture or detail seems to be in the distance Ø6. Atmospheric perspective - e.g., distant mountains often look blue (wavelengths)

Pitch and amplitude

Pitch: the psychological experience that corresponds with the frequency of an auditory stimulus (e.g., piano - when hammer strikes a short string on right end of the piano - high and on the left end there are longer strings - lower) Amplitude or intensity: total energy of a sound wave, and determines loudness of a sound (high have more energy)...measured in decibels (decibel scale) Timbre: complexity of a sound (the specific mix of amplitudes and frequencies that make up the sound) Amplitude is the vertical size of the sound wave, amount of compression and expansion of the molecules in the conducting medium, primary determinant of the sound's perceived loudness, differences are measured in decibels (measure of the physical pressures that occur at the ear drum), absolute threshold is arbitrarily designated as 0 decibels and each increase in 10 decibels represents a 10 fold increase The decibel scale relates a physical quantity (sound intensity) to the human perception of that quantity or sound loudness, it is a logarithmic scale

Smell-olfaction

Smell is a chemical sense and it is remarkably sensitive (there are about 10,000 different scents). Chemicals must move toward the receptor cells located on the walls of the nasal passage; when it moves past the receptor cells and is partially absorbed in the mucus, the process of smell is initiated. At the top of the naval cavity is the olfactory epithelium (layer of cells containing olfactory receptor cells); the message goes from there to the olfactory bulbs (enlargements at end of olfactory nerve) and then to higher centres of the brain for perception. Smells are very individualistic; what one person loves, others dislike. I remember when Axe (the male cologne) was popular. I could barely breathe walking down the university hallways as it was so horribly smelly - sometimes it made my eyes water it was so strong. For me, it was repulsive not attractive at all. Sense of smell is important for many species but human are visual creatures, blood hounds have poor eyesight but strong scent- 200x stronger than us, receptors for smell are long cells that project through the lining of the nasal passageway into the mucus membranes, humans have about 40 million receptors, dogs have 1 million, it is not well understood how we can distinguish between scents- theory says that olfactory cells recognize diverse odours individually rather than by mixing the information from small receptors, receptors are similar to neurotransmitter binding sites- odour molecules can look into sites that are tailored to fit them, receptors send their impulse to the olfactory bulb (above nasal cavity), each odorous chemical excites only a portion of the olfactory bulb- odours are coded based on where the olfactory bulb is stimulated, social and sexual behaviours of animals is more regulated by olfaction than human behavior- humans typically do not, pheromones may affect human behaviour, menstrual syncing, Pheromones- heat in animals, people try to take it to become sexually irresistible

taste

Taste can be very complex and is usually studied from bottom up (processing). It is a chemical sense; food is partially dissolved in saliva and stimulates the taste buds (primary receptors for taste found on small bumps on the tongue - papillae). Each hill is surrounded by a "moat"; on the walls of the moat are the taste buds (microscopic). Each of about 10,000 taste buds consist of 5 - 150 taste cells (last 10 to 14 days and are constantly renewed). Think back to when you "burned" your tongue on something hot and had diminished taste buds for a number of days before your taste can back. There are five basic tastes: sweet, sour, salty, bitter, and umami. Some people are more sensitive to certain tastes than others; many people do not like hot spices while others love them. With sensory adaptation, there are temporary changes in receptors. Something that is very salty will become "less salty" tasting as you continue to eat it; the same happens with spicy foods. The first bites are the spiciest and then the receptors adapt. Gustation (taste) and olfaction (smell) have receptors that are sensitive to chemical molecules rather than forms of energy, intertwined, taste experiences combine the basic tastes and information from other senses (smell, temp, touch- on the tongue), how we consume food affects how it tastes- bottle vs plastic, taste buds are concentrated along the sides and the back part of the tongue, each taste bud is most responsive to one or two of the basic taste qualities but responds weakly to the other ones as well, umami- increases the sensitivity of other taste qualities, sensory response activated by certain proteins and BiMSG- restaurants for flavour, humans have 9 000 taste buds each with receptor cells that are arranged like the segments of an orange, taste buds on back and roof of mouth, hair like structures project out through the taste pore onto the outside of the tongue, substances taken in from the mouth interact with saliva, taste- complex pattern of neuronal activity

The Forebrain (Diencephalon)

The Forebrain is the most advanced brain structure (organizationally and structurally); it is the largest and most complicated because of many interrelated parts (thalamus, hypothalamus, limbic system, basal ganglia, corpus callosum, cortex). Size and complexity of brain, L/R hemispheres that wrap around the brain stem, outer portion has thin covering or cortex, important structures buried in the central portion of the hemispheres

Midbrain (Mesencephalon)

The Midbrain is the least understood area of the brain. It is a very small structure that consists of nuclei (collections of cell bodies) that receive afferent signals from other parts of the brain and from the spinal cord; it interprets the signals, and either relays the information to a more complex part of the brain or causes the body to act at once. It has two divisions: - inferior colliculus (auditory) and superior colliculus (visual) - reticular formation and areas important for sensorimotor function and pain mediation It also governs smoothness of movement, temperature regulation, and other reflexive movements (e.g., movement of eyeball in the socket is the superior colliculus); the substantia nigra is involved in the smoothness of swinging a bat or getting out of a chair. Just above hindbrain, cluster of motor and sensory neurons and nerve fiber tracts, connects higher and lower portions of the nervous system, sensory- important relay centers for the visual and auditory systems- nerve impulses from eyes and ears are sent to forebrain structures that are involved in perception, motor neurons that control eye movement Buried within the midbrain is a finger shaped structure that stems from hindbrain up into the lower portion of the forebrain, under microscope- looks like reticulyte- alerts higher centers of the brain that messages are coming and blocking them or allowing them to go forward, descending- higher functions can admit or block out sensory input, central role in consciousness, sleep and attention, ascending reticulyte formation- prepares higher centers of the brain- without this, sensory messages do not register in the conscious awareness even though the appropriate nerve impulses may reach the appropriate higher area- brain is not awake enough- anesthetic- pain impulses are not registered in the sensory part of the brain, electrical stimulation in reticulyte formation can alter sleep, damage= permanent coma

Thalamus and hypothalamus

The Thalamus acts primarily as a relay station for sensory information; it integrates and analyzes this input and sends information on to the primary sensory cortex. All sensory information, except olfaction - smell, is processed by the thalamus. Above midbrain, two small footballs- one in each hemisphere, important sensory process relay station- sensory board- relays to correct part of the brain, visual, auditory and body senses, balance and equilibrium, different sensory responses go to different parts of the thalamus - synapse with other neurons to create perceptions , active dynamic filter that determines what gets sent to the higher brain, smell does not go to the thalamus The Hypothalamus contains numerous connections with rest of the forebrain and the midbrain. It influences "species-specific" functions such as eating, drinking and sexual arousal. It plays a huge role in maintaining the body's internal environment (homeostasis - body's internal equilibrium - or balance in blood sugar levels, body temperature); when temperature gets too low you shiver. The Hypothalamus is also involved in regulation of the endocrine system. Under the thalamus, tiny neuronal cell bodies that lie above the roof of the mouth, controls basic biological drives- sexual behaviour, temp regulation, eating, drinking, aggression and the expression of emotions- damage disrupts all of these functions, connections with endocrine system- pituitary gland- master gland that exerts control over all other glands, hormonal secretions, regulation of sexual development and behaviur, metabolism and reactions to stress

Neurons

The functions of each will be explained in the following slides. Neurons can vary greatly in size and shape- 200 different types, axons can be different lengths, but share overall structure and function Brain contains 85 million neurons Dendrites- far side and look like tree branches, receive info, receptors to pick up signals from neurotransmitter, signal causes electrical changes in the neuron, interpreted by the soma (cell body) and contains the nucleus, tales all the information and puts in the axon hillock, then signal to axon (action potential), myelin- insulative sheath that prevents the axon from degrading, axon terminals (synaptic buttons), release of neurotransmitter, repeats with next neuron

Myelin Sheath

The myelin sheath is the white, fatty coating around the axons of some neurons that helps insulate and speed neural impulses. It also prevents contact between the axon membrane and the extracellular fluid, eliminating the flow of current across the membrane in the myelinated region. Since fat serves as a good insulator, the myelin sheaths speed the rate of transmission of an electrical impulse along the axon. So... The importance of myelin sheath becomes readily apparent in certain diseases such as multiple sclerosis (MS) where the myelin progressively deteriorates loss of insulation around the axons leads to disruptions in the flow of information between the brain and muscles, and the person gradually loses muscular coordination can be fatal if it strikes the neurons that control basic life-support processes such as breathing or the beating of the heart Derived from glial cells during development- plastic covering over wires, interrupted at certain intervals at the Nodes of Ranvier where the myelin sheath is very thin or absent, nodes- make it look like sausage, unmyelinated- action potential travels the axon length like a burning fuse, myelinated- electrical conduction can skip from node to node so fewer action potentials need to be produced- high conduction, typically in higher animals, not completely formed until after birth- gains in infant development (walking)

Touch-tactile system- skin

The skin is approximately 2 square metres (it is the body's largest organ). It is comprised of a number of layers. The outer epidermis is made up primarily of dead cells and varies in thickness; the face is relatively thin while the elbows and heels are thick. It constantly regenerates (28 days). Touch is important- temperatures and pain- alerts us to dangers inside and outside our body, tactile sensations are also pleasurable (sexual), lack of tactile stimulation from an adult can slow development, sensitive to four tactile sensations- pressure, touch, pain, warmth and cold- conveyed by receptors in our skin and internal organs, mixtures of sensation cause all other issues (itch) The dermis (derma means skin) are live cells as well as nerve endings, blood, hair cells, and oil producing (sebaceous) glands. The hypodermis is a thick insulating cushion (fat); when you are older this layer gets thinner resulting in the wrinkles of the skin of older people. The Dermis and epidermis are resilient, flexible, and quite thick; they protect the body against quick changes in temperature and pressure. The epidermis also protects against pain from small scratches, cuts and bumps. Little is known about, skin is multi-layer elastic structure that covers 90 cm2 and weighs between 2.7-4.5 kg, largest organ in body, variety of receptor cells- sensations are patterns of activity of the receptors, primary receptors for pain and temperature are free nerve endings- simple nerve endings beneath the surface that resemble the bare branches of a tree, nerve fibers at the base of hair follicles are receptors for touch and light pressure, brain can locate sensation because receptors send impulse to specific spot in the somatosensory cortex, fingers, lips and tongue are extremely sensitive- well represented ØEpidermis: outer layer (primarily dead cells and varies in thickness) Ø ØDermis or "derma": live cells as well as nerve endings, blood, hair cells, and oil producing (sebaceous) glands Ø ØHypodermis: thick insulating cushion

Sound Localization

When you are standing somewhere, sound will reach the closest ear first resulting in an interaural time difference(sound at left reaches left ear before right ear due to distance). It is also more intense in left than right (interaural intensity difference). Sounds are analyzed in the brain at nuclei sensitive to them. Sound localization depends on the body and head movement, as well as ear shape. Hard of hearing 16% of adults and more than 1/3 of those over 60 (4/100 Canadians) have hearing difficulties. Sometimes this stereotype results in discrimination as people conclude those that can't hear actually is due to a lack of intellect. This about how you talk to older people; do you raise your voice, talk slower, speak as if you were speaking to a child or someone of lesser intelligence? Even worse, do you talk "baby talk" which can be incredibly condescending. Deafness can result from a variety of reasons. Conduction deafness: deafness resulting from interference with the transmission of sound to the neural mechanism of the inner ear. Sensorineural deafness: resulting from damage to the cochlea, the auditory nerve, or higher auditory-processing centres; most common cause is exposure to very high intense sound - rock bands at concert...jet planes...headphones that are too loud). Sound that is moderately loud for over 15 minutes can cause permanent damage; now many businesses require their employees to wear ear protection, something that did not happen in the 20th century. Audiometer: presents sounds of different frequencies through a headphone, measures hearing loss results (audiogram - graph showing hearing sensitivity at different frequencies). It is important to get hearing tested if someone seems to be having difficulties. Canada- 3 million suffer from some form of hearing loss, NA- 23 million, conduction- mechanical structure problem that transmits sound waves to the ear- ear drum issues can prevent the eardrum from transmitting vibrations- hearing aid amplifies the sound, nerve damage- damage to receptors in the inner ear or damage to the auditory nerve itself, cannot help with hearing aid, caused from repeated exposure to loud sounds, lose hair cells on the basilar membrane

The retina

lHas a complex multi-layered organization consisting of a network of neurons lMost important are the photoreceptors(light sensitive cells) lAfter it passes through other layers, it strikes the photoreceptor layer (consists of rods - large rod-shaped receptors - and cones - small cone-shaped receptors) The retina has aptly been called an extension of the brain. It has several relatively transparent layers and contains 130 million photoreceptor cells that convert light energy into neural activity. Cones are shorter, thicker more tapered cells that are sensitive to color under high levels of illumination. Cones are densely clustered in the center of the fovea, the pinhead-size center of the retina. Unlike the rest of the retina, the fovea contains only cones, and the ratio of rods to cones increases in the outer edges of the rods. We have about 7 million cones. This enables us to see colors under normal lighting. Owls and other nocturnal animals don't have any cones - they can see in night but it is only in black and white. Each eye contains more than 120 million rods as well. Rods are used for night vision. Rods and cones do NOT have individual pathways to the higher visual centres in the brain. ØHere light energy is transformed into electrical energy in a process called transduction or coding and transferred from the rods and cones to the bipolar cells; convergence (electrochemical signals from many rods come together into a single bipolar cell - same with cones) ØThen to the ganglion cell layer of the retina ØThe axons of the ganglion cells make up the optic nerve (carries messages to the brain) Instead through CONVERGENCE light energy is transferred from many rods and cones to the bipolar cells. From the bipolar cells, electrochemical energy is transferred to the GANGLION CELL LAYER of the retina...dozens of bipolar cells synapse and converge on each ganglion ell (approx. 1,000,000 ganglion cells). The AXONS of the ganglion cells make up the optic nerve (carries messages to the brain) to the optic chiasm (crossover point) to the lateral geniculate nucleus. Rods and cones send their message to the brain via two additional layers of cells, bipolar cells have synaptic connections- bipolar cells synapse with ganglion cells- whose axons are bundled together to form the optic nerve

Dendrites

little tree, receive electrochemical information and transmit to cell body, Dendron is the Greek work for tree. Dendrites are branching neuron structures that receive neural impulses from other neurons (over the synapse) and convey impulses to the cell body. They are covered in dendritic spines (small thorn-like protuberances [things that protrude from something] that form the post synaptic element of most synapses. Dendrites change over the length of the dendrite (the greater the distance - the larger and more elaborate they become). Dendrites come in many different shapes and sizes. Dendrites change over the length of the dendrite (the greater the distance - the larger and more elaborate they become). Dendrites come in many different shapes and sizes.

How do they study JND?

method of limits: various values of a stimulus are presented in ascending or descending order (e.g., lights of low intensity, slightly higher...slightly higher, etc.) method of constant stimuli: values of a signal are presented in random (not ascending or descending) order; person must respond yes or no, indicating that he or she has either detected a stimulus or not - both of these methodologies have weaknesses in that they DO NOT allow for key factors in the human observer - - people may report when they can't detect something to appear competent and cooperative Signal Detection Theory: holds that an observer's perception is dependent not only on the intensity of the stimulus but on the observer's motivation (e.g., worried about a friend being late, you listen more for his/her car). This perception is dependent on the level of auditory stimulation needed to state "that is a car". It is also dependent on the NOISE (constant background activity present) David Green and John Sweats developed signal detection theory to describe how we detect stimuli under uncertain conditions- what is a friend saying on a phone when there is a lot of static in the background, increase signal by shouting over static or our friend will not understand us, good connection- friend can easily understand us without shouting- demonstrates the signal to noise ratio--- negative correlation

Apophenia and Pareidolia

uApophenia: tendency to perceive meaningful connections among unrelated phenomena, In psychology, Apophenia is the perception of connections and meaningfulness in unrelated things. Apophenia can be a normal phenomenon or an abnormal one, as in paranoid schizophrenia when the patient sees ominous patterns where there are none. Pareidolia: tendency to perceive meaningful images in meaningless visual stimuli, Pareidolia (/pærɪˈdoʊliə/ parr-i-DOH-lee-ə) is the tendency for incorrect perception of a stimulus as an object, pattern or meaning known to the observer, such as seeing shapes in clouds, seeing faces in inanimate objects or abstract patterns, or hearing hidden messages in music. Whilst pareidolia is not usually related to a mental illness, it can be experienced in schizophrenia. For example, if seeing faces in inanimate objects starts to bring up emotions such as fear or anger, that's when pareidoliacan start to get out of control and take over your life

Scientific skepticism

uApproach of evaluating all claims with an open mind but insisting on persuasive evidence before accepting them A basic framework for scientific skepticism is critical thinking (not a tendency to attack all claims) but is a set of skills for overcoming our own biases (or scientific thinking) uPsychological research and scientific thinking offers important applications for a variety of aspects in our lives: uBasic research: examines how the mind works versus uApplied research: examines how we can use basic research to solve real-world problems Open mindfulness drive inquiries, curiosity, skeptic- show evidence, asks might there be a better explanation, open to conclusions that are supported by facts even if the conclusions refute their own beliefs

Confounding variables

uAre variables that can create one set of potential alternative explanations by exacting extraneous (outside) influence during an experiment that can unwittingly affect environmental results; if not controlled for researchers cannot be certain whether the experimental manipulation, or a confounding variable, is responsible for the results (e.g., IV is a new blood pressure [BP] pill but what if the patient changes their diet or loses weight - may not be the pill that causes lower BP), variables that could influence the results and cause the change being studied

Correlational methods or measuring associations between events

uDetermine the extent two variables, traits, or attitudes are related Correlation coefficient (statistic of standard measure of correlation) is represented by "r" (can vary between -1.0 and +1.0: 0 (zero) means no relationship exists) Correlations: the tendency for one aspect of the world (or one variable) to change with another aspect of the world (or variable) Correlational Co-efficients - not cause and effect - -1.00 to 0 to + 1.00 - look for direction (is it negative or positive) and strength (how close to 1.00 is the number (the # indicates this) - positive correlations (as one increases the other increases)/negative correlations (as one increases the other decreases) -a strong correlation (stress and cancer); a weak correlation (cell phones and brain cancer) - -correlations are very vulnerable to third-variables (confounds) and reverse causality problems in interpretation uPositive correlation: as one variable increases so does the other u uNegative correlation: as one variable decreases the other increases u uCorrelation DOES NOT imply causation

Two types of confounds that apply to almost all experiments

uExpectancy effects: occur when a researcher subtly communicates to the participant the results that he or she expects, because participants and researchers expectations can influence the results, participants should not know whether they are in the experimental or control group; the researcher, because of their expectations and high hopes for a particular result may cause them to inadvertently influence the participants uPlacebo effects: occur when human participants' beliefs about the efficacy of a procedure lead to improvement in the participant, a placebo is an inactive substance or fake treatment used as a control in an experiment or given by a medical practitioner to a patient

Experimental Methods in psychology

uExperimental method: used to overcome causal ambiguity (manipulates an independent variable and then looks at the effect on the dependent variable) uInitial explanations often lead to alternative explanations (the more there are the less confident a researcher can be that his or her predicated explanation or hypothesis is the correct one) Experimental group: receives the treatment or active level of the independent variable, control group: not exposed to the treatment, zero level of independent variable, create a standard of behaviour through which the experimental group can be compared

Systemic Observation

uGo into the field, or natural observation, and record the behaviour of interest (naturalistic observation) uLimitation: not all will display behaviour of interest uStructured observation: researcher sets up a lab situation that evokes the behaviour of interest so that every participant has an equal opportunity to display the response uLimitation: may be difficult to observe the behaviour of interest (e.g., bullying) Naturalistic Observation: In naturalistic observation, the researchers watch how animals or humans behave in their natural environment. The major advantage or strength is that it provides a realistic picture of behaviour. There are three disadvantages or limitations of naturalistic observation. Naturalistic observation may not be possible. This is known as the "observed effect or Hawthorne Effect". Hawthorne Effect - individuals act differently when they know that they are being observed (this definitely comes in to play in research as the people being studied may not behave the way that they normally would). An example of this is red light cameras and the cameras in the gyms to prevent cheating. Are they always turned on? We aren't certain if they are watching or not and therefore we may not perform the behaviour of running the red light or cheating. To decrease this effect, participant observation is used. In participant observation, the observer becomes a participant in the group being observed. In this way, the group gets used to having this person around and is more likely to behave as they normally would. Structured Observation: Field experiments: an experiment conducted in a natural, real-life setting, outside the laboratory. Realism of the setting allows for greater generalizability, but control may be sacrificed Lab experiments: an experiment conducted in a carefully controlled environment that simulates real-life settings. High degree of control is possible, but external validity may be sacrificed - not what would happen in the real world. In laboratory observation, researchers watch how animals or humans behave in a lab setting. The major advantages or strengths of lab observation are that it allows researchers to have greater control over the environment in which they observe participants and that it allows the use of specialized equipment. The disadvantage or limitation of laboratory observation is that the artificial situation that a lab presents may result in artificial behaviour by participants

Evolution of large brains

uHumans possessed several characteristic that enabled them to compete with other species: agile hands, excellent colour vision, mastery of fire, upright posture and bipedalism, linguistic abilities - these characteristics required a larger brain uA large brain requires a large skull, and an upright posture limits the size of a woman's birth canal. A newborn's head is about as large as it can be. Because a baby's brain is not large or complex enough to perform the physical and intellectual abilities of an adult, it must continue to grow after the baby is born. uThe evolutionary process did not have to produce a brain with specialized circuits that performed specialized tasks; instead, it could simply produce a larger brain with an abundance of neural circuits that could be modified by experience

Standardization: the remedy for observer bias

uMeans using uniform procedures in all phases of the research process (i.e., all participants should experience the same procedure, and other researchers should be able to replicate the procedure exactly) An operational definition explains a variable of condition in terms of its measurement, operation, or procedure used to determine its existence in the research setting Operational Definition - a clear, precise statement of the operations that are used to measure the concept. This is very hard to do as some concepts are very vague (e.g., love, justice, poverty, bullying, etc.) Therefore, operational definitions translate abstract concepts into something observable and measurable (e.g., bullying will be operationalized in this study as how many times someone physically hits someone else). uA variable is any factor in an experimental setting that varies in amount or kind (e.g., depressive mood - from mild to severe) u uIndependent variable (IV) - manipulated by the experimenter and are free to vary (experimental group - receives manipulation - versus control group - does not receive manipulation) u uDependent variable (DV) - whose values result from changes in the independent variables (those that are MEASURED)

Evolutionary theory- natural selection

uOne of the major influences on functionalism was the work of Charles Darwin; in 1859 he published "On the Origin of Species" u uThe basic units of natural selection are genes which are passed on to offspring uRandom natural mutations occur; individuals with these adaptations are more likely to survive uAs more and more people acquire these adaptation a species will change (evolution) All characteristics have functional significance Behaviour is NOT inherited- what is inherited is the brain that causes the behaviour to occur Functionalism Characteristics have useful functions Understand natural behaviours of the species so that behaviours can be seen in context Natural selection allows for more of the species/offspring to have the specific trait Mutations- accidental changes in the chromosomes of sperm or eggs that develop into organisms, most are not good- offspring either fail to survive or have some sort of defect, resistance to disease, digest new foods, defence mechanisms, mating patterns uTo "evolve" means to develop gradually (from the Latin evolvere "to unroll") u uEvolution: a gradual change in the structure and physiology of plant and animal species - generally producing more complex organisms - as a result of natural selection hominids, hunters and gathers, made tools, similar to chimpanzees, homo Erectus, Neanderthals

6 possible mistakes that can occur in research

uPopulation error: this can occur when the researcher incorrectly chooses the population of people to be studied uSample error: this can occur when a study is run using participants who have been incorrectly selected from a correct population (the sample must be representative of the larger population that is the interest of examination - when the sample is representative of the population of interest then the results can be generalized to that population) uMeasurement Bias: can occur when we use tools or methods of gathering information that are not valid (measure what they should be measuring) and reliable (under the same conditions, it gives the same results every time it is used) uObserver Bias: occurs when we see what we expect to see (and ignore that we don't expect to see) uHindsight Bias: the false belief that you always knew something; we experience this after the event has occurred uFalse Consensus Effect: the false belief that people share our beliefs and behaviours Population: all the individuals about whom we are interested in drawing a conclusion, generalize results, cannot study everyone—sample: subset drawn from the population of interest, must be representative- reflect the importance of characteristics of the population

Research Designs

uProperly designed experiments ensure that alternative explanations are kept to a minimum uRandom assignment: one of most important aspects of research design (helps ensure the participants are similar in each experimental condition as each participant has the same chance of being in each condition) random sampling - a procedure for assigning people to experimental and control groups, in which each individual has the same probability as any other of being assigned to a given group. For example, I could just go around the room saying: Group A and Group B or you could pick a pebble out of a hat - Group A is the white pebbles and Group B is the brown pebbles. Each person has a 50/50 chance of being in whichever group. Random sampling increases the likelihood that the research sample will be representative of the population. However, this is not always true uPopulation: entire group of individuals to which researchers will generalize their conclusions (usually impossible) so... uRepresentative sample (a subgroup with similar characteristics as the larger population) from the population of interest in order to generalize research results These are subject to errors Sample Size --Sample size matters - the larger the number the better for statistical significance. Samples are chosen to represent a POPULATION that you want to be able to generalize the results to. uBetween-subjects designs: participants are randomly assigned to experimental group(s) or control group(s) u uWithin-subjects designs: each participant serves as his or her own control group (exposed to both control and experimental conditions - e.g., measure fitness before starting the experimental program and then again after the program is completed) Between: different set of participants but must be equivalent at the beginning of the study, random assignment, within: you are the control- weight before and after weight loss program

Levels of Analysis

uRungs of a ladder of analysis, with lower levels tied most closely to biological influences and higher levels tied most closely to social influences u uA. Biological - molecular or neurochemical (involves brain systems, neurochemistry and genetics) u uB. Psychological or Individual - individual differences, perception and cognition, behaviour, including thoughts, feelings, and emotions) u uC. Social Influences - social or behavioural level (involves relating to others, and personal relationships) u uD. Cultural Influences - thoughts, actions, behaviours in different societies and cultural groups Looking at the levels of analysis and using the analogy of a ladder, we see that the lower levels are tied to the brain (the biology) and the higher levels are tied to the mind...according to the textbook the authors say that it refers to the same stuff. I am not so sure as I believe in dualism (that they are separate but connected). To fully understand psychology though, we do need to consider the multiple layers of analysis as both the biological and social/cultural factors are required. Human behavior is very complex. I will use an example (depression) to explain how each of these levels works with this topic. Beginning with the biological level, in some cases there are genetic factors associated with depression (it does run in some families). Also, there are neurotransmitters (brain chemicals) that are involved in depression, most prominently serotonin and norepinephrine. Low levels of Vitamin D have also been implicated as having a depressed mood effect on people. Moving up to the psychological level, there is evidence to suggest that people's patterns of thinking (their cognitions) have a bearing on depression. Some people interpret information in a pessimistic way (negative). It could be that some personality patterns are more prone to depression than others (e.g., perfectionism, low self-esteem, lack of "mattering'). In social influences, we know that depression is related to people's childhood histories of abuse, parental rejection and family difficulties. People who have been subjected to great losses may develop pessimistic personalities that predispose them to become depressed further down the line. People often stop doing things that used to bring them pleasure and then their social lives worsen. According to the sociocultural environment, depression is found in all cultures but may reflect cultural differences behind the depression. Canada has a somewhat lower rate of depression than other Western countries but women are more susceptible than men. I hope that example helps.

Evolutionary Psychology

uSeeks to explain how evolution shaped modern human behaviour (Buss, 2005) u uStresses that human mental abilities and behavioural tendencies evolved along with a changing body u uAlso attempt to explain human social behaviour u uSociobiology: holds that complex social behaviours are also built into the human species as products of evolution (controversial) Human ancestors had certain abilities (walk upright, use hands, etc.), thought, language and ability to solve problems became more important Sociobiology- natural selection increases the ability to pass on one's genes to the next generation- aggression, competition and dominance in males, cooperative and nurturing tendencies in females- greater investment in the reproductive aspect, primary caregiver after divorce, once there is transmission of one's genes is more important that one's own physical survival- altruistic behaviors such as giving up one's life to save children/relatives, may overemphasize innate biological factors at the expense of cultural and learning factors- evolved brain structures that underlie psychological mechanisms are developed to enhance adaptation to demands of social and group living rather than simply to further the survival of one's genes

Sigmund Freud

uSigmund Freud was a Viennese neurologist; focused on unconscious processes u ubehaviour is driven or motivated by powerful instincts, biological drives, and attempts to resolve the conflicts between personal needs and society's demands; an organism will stop reacting when its needs are satisfied and its drives reduced - the main purpose of action is to reduce tension or anxiety u uFreud's Psychosexual Theory was very controversial The Psychodynamic perspective holds that behavior results from powerful unconscious inner forces. These forces include innate instincts, biological drives, and attempts to resolve conflicts between personal needs and societal demands. The purpose of behavior, according to Freud, is to reduce this tension. Freud emphasized that the early childhood is an important timeframe during which one's personality is formed. Psychodynamic principles have since broadened to include the role of social influences and interpersonal interactions over the life span.

Naïve realism

uThe belief that we see the world precisely as it is u uWe know that our perception is affected by many different factors, including u uEthnocentrism: we see the world through our own ethnocentric worldview (we have been raised a certain way with certain belief systems and we use these to judge the outside world - and even sometimes ourselves) uConfirmation bias: the tendency to seek out evidence that supports our hypotheses and deny, dismiss, or distort evidence that contradicts them uBelief perseverance: tendency to stick to our initial beliefs even when evidence contradicts them Even though our perceptions are often correct, we can't always trust them to give us an error-free picture of the world. We often assume that "seeing is believing" yet we have biases that affect how we "see". We all possess our own ethnocentric point of view that comes from our experiences in the world; we have been raised with certain belief systems (e.g., religious beliefs or political beliefs) and we use those to judge the outside world. We believe that our way is the right way and that others are "wrong" or faulty in their beliefs. We judge others according to our ethnocentrism. An example is with vegetarianism. If we are meat eaters and possibly make a living raising cattle, we are going to judge vegetarians as incorrect because "everyone needs to eat meat for their protein" and possibly that "they are making it tougher for us to make a living". However, if you were raised vegetarian then you would think that meat eaters are wrong as they kill animals (could also be that they aren't animal rights activists but believe that a vegetable diet is far healthier). They will judge the meat eaters as incorrect. The confirmation bias also comes in to play because we do have a tendency to seek out research and other information that supports our position (and we don't seek out that which contradicts our position). So...we will find information on how we need to eat meat in order to get our daily requirement of protein; we may also find information on the detriments to health of not eating meat. We will also find information on why vegetarianism is very healthy for us and research on the inhumane treatment of animals in the meat industry.

Functionalism

uThe perspective of mind and behaviour that focuses on the examination of their functions in an organism's interactions with the environment and how the organism adapts to its environment; for functionalists, the key questions was "What is the function or purpose of any behavioural act?"; inspired by Darwin, they asked how various actions help a person or animal adapt to the environment The functionalists wanted to understand the adaptive purposes, or functions, of psychological characteristics, such as thoughts, feelings, and behaviours. The structuralists asked "What?" and the functionalists asked "Why?" The functionalists were influenced substantially by Darwin's theory of natural selection which emphasized that physical and behavioural characteristics evolved because they increased chances of survival and reproduction. It does not exist today in its original format but has been absorbed in to mainstream psychology

Clinical or case study

uWide range of information on one person u uWell-suited for studying rare situations/cases (e.g., brain injuries, extremely gifted children, various rare syndromes) uGain valuable information usually very detailed and a holistic way of looking at the individual (e.g., we have learned a lot about serial killers but studying individuals - we cannot randomly assign people to be serial killers; we have learned about rare syndromes by studying in depth individuals with those syndromes). We cannot generalize the findings however. Advantages: 1.When a rare phenomenon occur, this method enables scientists to study it closely 2.A case study may challenge the validity of a theory or widely held scientific belief 3.A case study can be a vibrant source of new ideas and hypotheses that subsequently may be examined by using more controlled research methods ● Limitations: 1.They are a poor method for determining cause-effect relations 2.Case study findings may not generalize to other people or situations 3.Observers may not be objective in gathering and interpreting the data (subject to observer bias) in depth analysis of an individual or group or event- discover principles of behaviour that are true for situations and people in general, data- interviews, psychological tests, observations, physiological recordings, task performance, archives, provide insight in to diverse topics, failure to thrive- poverty, treatment program to help mothers, generalization of a principles- more case studies, other research methods, test variety of cultural groups, claims need to be followed up in control methods before they are excepted

Balance

ØSemicircular canals: three fluid-filled canals in the inner ear responsible for our sense of balance Ø ØKinesthesis: the awareness aroused by movements of the muscles, tendons and joints Ø ØProprioception: body position sense Ø ØVestibular Sense: the sense of bodily orientation and postural adjustment We use proprioceptive cues (proprioception) - sensory cues coming from within your body that provide information about bodily movements and internal sensations. Our Vestibular Sense is the sense of bodily orientation and postural adjustment (in ear). Vestibular sacs and semicircular canals (cochlea) in our ears provide information about orientation of our head and body (balance beam, after diving, etc.). When you are experiencing rapid movements....do not close your eyes or you will get dizzy; instead focus on one spot. Ever wonder how figure skaters don't get dizzy after doing all of their spins and then just carry on with their program? Kinesthesis- able to coordinate muscles, provides us with feedback about muscle and joint positions and movements, receptors are nerve endings in the muscles, tendons, and joints, this basis helps us to coordinate

Self-reports

uWritten or verbal (questionnaires, surveys, interviews) uPeople provide information about their perceptions, thoughts, abilities, feelings, attitudes, beliefs, and past experiences uLimitation: must rely on honesty and memory that may be faulty There are a number of problems with self report including the fact that people lie sometimes due to social desirability bias or the tendency to want people to think good about us (when asked whether they have ever picked their nose, most people say "no"; however we were all children and children spend a lot of time with their fingers up their noses). Another problem may be acquiescence or the tendency to say yes; the same question should be asked twice (once where the respondent should answer yes and the opposite when they should answer no - if they don't then they are either not paying attention or acquiescence is in play). Questionnaire/Survey: - may be expensive although now with computer questionnaires (e.g., SurveyMonkey) if can be a bit cheaper -if using paper questionnaires then coding requires a lot of time however again with SurveyMonkey the data can be input electronically - Interviews: -can be structured (only certain questions are allowed and in a certain order - no qualification or explanation is allowed), semi-structured (there are questions but qualification or explanation is allowed and the order can be varied) or open format (no formal questions - people just "talk") -you can get a lot of information and usually in-depth information -Interviews, questionnaires, hinges on the response and willingness to respond honestly, social desirability- what we think society wants to hear rather than how we actually feel- word questions so that it is not relevant, autonomy and confidentiality, familiarity,

Gestalt Psychology

uan alternative to structuralism was pioneered by Max Wertheimer, a Frankfurt University psychologist, who focused on gestalts - organized wholes - "the whole is different from the sum of its parts"; another researcher in this area is Wolfgang Kohler In the 1920s, German scientists (e.g., Max Wertheimer and Wolfgang Kohler) formed a school of thought known as Gestalt Psychology; it examined how the mind organizes elements of experience into a unified or "whole" perception. Gestalt roughly translates as "whole" or "organization". These scientists agreed that perceptions are organized so that "the whole is greater than the sum of its parts".

Humanistic Perspective

uholistic psychological model that emphasizes an individual's phenomenal/experiential world and inherent capacity for making rational choices and developing to his/her maximum potential; believed that humans are active, innately good creatures who are capable of choice or free will u uRogers is the founder of Humanistic Psychology (he is discussed more fully in Personality, Abnormal Behaviour and Therapies in Psych 101); Believed that clients should be shown Unconditional positive regard (accepting people for exactly who they are) And Client-centred therapy u uMaslow coined the term self-actualization (an individual's drive toward the fullest development of his or her potential) u uHumanistic Psychology expanded the realm of psychology to include valuable lessons from the study of literature, history, and the arts Humanistic psychology emerged in the 1950s, countering both psychodynamic and behaviourist perspectives. Humanists suggested that humans are not controlled by unconscious drives or the external environment, but that they have choice or free will. The main task of humans is to strive for growth and development of their potential. Humanists are phenomenologists in that they study the individual actor's personal view of events, focusing on the subjective world experienced by the person, not an objective reality. Humanistic psychology is holistic, not reductionistic (reducing to elements that drive behavior). It examines the human as a whole and does not attempt to reduce mental life to elemental parts. Positive Psychology focuses on individuals' character strengths (e.g., courage, wisdom, gratitude, etc.). Carl Rogers and Abraham Maslow were influential humanists. Rogers believed that humans have a natural tendency toward psychological well being and should be regarded unconditionally. Maslow also believed people maintained a drive toward maximizing their fullest potential; he coined this term self-actualization.

Wilhelm Wundt

uin 1879, Wilhelm Wundt established the 1st psychological laboratoryin Leipzig, Germany; he was trained in medicine and philosophy and promoted "trained introspection" u uEdward Titchener brought Wundt's psychology to NA (Cornell University) and advocated that scientific methods be used to study consciousness using introspection or the systematic examination by individuals of their own thoughts and feeling about specific sensory experiences u uHe emphasized the WHAT of mental contents rather than the WHY OR HOW u uthis approach became known as structuralism (the study of the structure of mind and behaviour); its goal was to reveal the underlying structure of the human mind by analyzing the component elements of sensations and other experiences that form an individual's mental life George Humphrey- experimental psychology research in queens, Edward Tichener, Wundt's student originally from Britain, emigrated and became an influential early psychologist with his laboratory at Cornell University in the USA, founded in 1892. This perspective became known as Structuralismaimed to identify the basic elements or "structures" of psychological experience- break down mind into simple components, Structuralism was based on the assumption that all human mental experience could be understood as the combination of simple elements and the goal was to reveal the underlying structure of the human mind by analyzing the basic elements, similar to the periodic table of physical elements used by chemists and physicists. These of course did not appear. Wundt's student- created lab at Cornell University),

Behaviourist Perspective

uprimarily concerned with observable behaviour that can be objectively recorded and with the relationships of observable behaviour to environmental stimuli u ubased on experiments by Russian Pavlov, John B. Watson argued that the whole idea of consciousness or mental life was "mere superstition" - "you cannot define consciousness any more than you can define a soul" (you can't locate it, measure it, and therefore it cannot be studied) u ustudy of observable, measurable behaviour is the only scientific study Behaviourists seek to understand how environmental stimuli influence behavior, reducing behavior into antecedents, behavioural responses, and consequences of behaviour. John Watson, known as the father of Behaviourism, studied observable behavior, often using animal to control the conditions of experimentation more completely than they can with human participants

Axon (axle)

•similar to a miniature cable, it carries information away from the cell body An Axon is a long, tube-like structure, often covered by myelin, that conveys impulses away from the neuron's cell body to the terminal buttons, toward other neurons or to muscles or glands. The basic message it carries is called The Action Potential (an electrical/chemical event that starts at the end of the axon next to the cell body and travels toward the terminal buttons). REMEMBER: DENTRITES (D) TO CELL BODY (C B) TO AXON (A) Transmits messages to other neurons or glands, axon terminals- may connect with other dendrites- messages can transmit through 50 000 neurons

Biological Perspective

ustrives to identify causes of behaviour by focusing on the functioning of genes, the brain, the nervous system, and the endocrine system u uthis contributes to the multidisciplinary field of behavioural neuroscience that attempts to understand the brain processes that underlie behaviour, and to cognitive neuroscience that attempts to understand the brain processes that underlie higher cognitive functions The biological perspective attempts to explain behavior in terms of the influence of genes, the brain, the nervous system, and the endocrine system by examining underlying physical structures and processes. From this perspective, even the most complex behavior can be understood by decomposing the behavior into smaller units, such as the firing of neurons in the brain (Chapter Three). One unifying theme in this perspective is that, although the environment and experience may modify behavior by altering underlying biological structures and processes, behavioiur originates from biological drives. Two areas are: Behavioural neuroscience, a multi-disciplinary field that attempts to understand brain processes that influence human cognitive functions such as sensation, learning and emotion. Cognitive neuroscience, a multi-disciplinary field that attempts to understand brain processes that influence human cognitive functions such as memory, language and learning.

The cognitive perspective

uthe perspective on psychology that stresses human thought and the processes of knowing, such as attending, thinking, remembering, expecting, solving problems, fantasizing, and consciousness uGeorge Miller was a founder of cognitive psychology as well as Ulric Neisser Cognitive psychologists are most interested in human thought and all the processes of knowing, such as attending, thinking, remembering, and understanding. They view behaviour as partly determined by past experiences but also influenced by an individual's inner world of thought and imagination. An individual's subjective reality is more important than the objective reality that behaviourists strive to capture. Cognitive psychologists often use the computer as a metaphor for the human mind and study higher mental processes such as perception, memory, language use, problem solving, and decision making.

What is Psychology?

uthe scientific study of behaviour and mental processes and how they are affected by an organism's physical state, mental state, and external environment uthe root of the word psychology (psyche) means "soul" or "spirit" in Greek uthe term is often represented by the Greek letter psi Scientific Method: this aspect requires that psychological conclusions be based on evidence collected according to the principles of the scientific method (discussed later) Behaviour includes the means by which organisms adjust to their environment. It is ACTION; in psychology a lot of the research utilized observation. Mental: those cognitive processes that individuals use to influence their action (this is a very important aspect of psychological inquiry and one of the hardest to study). Why? It is hard to study because: a. peope lie or do not report for various reasons; and b. people sometimes do not know what they are thinking or why they are thinking that way, etc.

Joseph Gall

was a very skilled brain anatomist who understood a lot about the gray and white matter of the brain and many of the structures. He also believed that the mind was located in the brain and that specific parts of the brain did specific functions. He was correct in that there are specific parts that do specific things however his theory that personality corresponded with bumps on the person's skull was not correct and was supposedly based on his observations of his classmates). Resistance to his ideas came from the fact that the shape of the skull does not reflect underlying brain and although there are specific areas such as Broca's area that is responsible for speech production, size does not indicate function. Phrenology became very popular in Europe and the USA in the early 1800s. Phrenology (study of the mind)

Synesthesia

ØA condition in which people experience cross-modal sensations , first described by Sir Francis Galton, is a rare condition in which people experience cross-modal sensations, like hearing sounds when they see colours - sometimes called "colour hearing" - or even tasting or smelling colours . The most common form of synesthesia is grapheme-colour synesthesia; a 6 may always seem red or a 5 green. In lexical-taste synesthesia words have associated tastes, and in other synesthesias, letters may take on "personality traits", such as a B being perceived as bold. Prevalence is no higher than 1 in 2000 people but some say higher than that. One group of researchers found that nearly 23% of fine arts students across three different universities displayed synesthetic abilities Metaphors, cross wiring in the brain- TPO, V4, ordinality (sequence) and cardinality (quantity), more common in creative people

Duplicity Theory of vision- duplexity theory

ØAssets there are two separate receptor systems in the retina (rods and cones) ØRods and cones are structurally different and have different tasks lCones for the most part on the fovea and used for day vision, colour vision, and fine visual discrimination (e.g., driver's test - visual acuity or resolution capacity); better in a brightly lit room lRods (together with some cones) are found on the rest of the retina and used predominately for night vision lDark adaptation is an increase in sensitivity to light that occurs when the illumination level changes from high to low Retina contains specialized sensory neurons, viewed as extension of the brain, rods function best in dim light and are black and white brightness receptors, more sensitive to light than cones, owls only have rods- great vision in dark but cannot see very well during the day, cones- function best in great illumination, only active during the day- chipmunk, pigeon, only have cones so see things in very bright colours during the day but have poor night vision, if active during day and night- mixture of rods and cones (humans)- rods are found throughout the retina except in the fovea, cones decrease in concentration as they move away from the fovea- peripherally mostly rods, like the rods, the cones that are in the periphery share bipolar cells, fovea- each has own private line to a single bipolar cell= visual acuity (see fine detail) happens when light lands directly on fovea, this causes a large firing of cones to their private lines, eagles, hawks have two foveas in each eye- they can see small prey on the ground

What approaches do researchers use to examine sensation and perception

ØBottom-up processing: lSensing of individual stimulus elements lBreakdown analysis of stimuli (including feature detection) lCombination and interpretation of whole Ø ØTop-down processing: lexamines complex perceptual phenomena from more complex interpretations or memories lfocuses on aspects of the perceptual process such as selective attention and active decision-making. lalso known as conceptually driven or hypothesis driven processing because the concepts you have stored in memory affect interpretation of the sensory data. Both are necessary and useful because sensation and perception involve whole sets of structures, functions, and operations by means of which people perceive the world around them.

Psychophysics

ØFocuses on the relationship between physical stimuli and people's conscious experience of those stimuli Ø ØThreshold: a dividing line, a point at which things become different Ø lIn perception, a threshold is the value of a sensory event at the point at which things are perceived as different Although we can measure the physical stimulus very precisely, its effect on the observer is not so simple. There are five major sensory receptors, which detect stimuli and, by converting energy into those action potentials we've talked about, create neural impulses that send messages to the brain. We'll go over the visual system, auditory system, the skin senses, smell, and touch. 19th century- sensation and perception, when psychology was being separate from philosophy, 1860- German scientist- Goostalf Feckner published a landmark work on perception- then grew psychophysics, how we perceive sensory stimuli based on physical characteristics

Theories of hearing

ØFrequency Theories: the analysis of pitch and intensity occurs at high centres (levels) of processing, perhaps in the auditory area of the cortex and that the basilar membrane merely transfers information to those centres ØPlace Theories: claim that the analysis of sound occurs in the basilar membrane, with different frequencies and intensities affecting different parts (places) of the membrane, each sound wave causes a travelling wave on the basilar membrane, which in turn causes changes in the hair cells - both of these theories have theoretical problems Frequency theory- nerve impulses sent to the brain match the frequency of the sound wave, 30 Hz cycle per second from piano should send 30 bodies of nerve impulses per second to the brain, problem- neurons are limited at their rate of firing, individual impulses are vollies of impulses followed by groups of neurons cannot produce high enough frequencies of firing to match sound wave frequencies of 1000 Hz, how do we perceive higher frequencies from the same piano? George von Vexine conducted experiments in 1957, cut tiny holes in the cochlea of Guinea pigs and human cadavers, wanted to see what the eardrum did when there were varying frequencies, lower frequencies create a slower fluid wave that peaked further down the cochlea channel, where it peaks and bends the hair cells serves as a frequency coding cue, specific locations on the cochlea help to code and interpret the sound

Receptive fields

ØHubel and Wiesel (1962) found that cells (on the retina) fire when stimulated in the centre of their receptive field but do not fire when stimulated outside the centre area (e.g., specific cells will fire if a vertical line is present or a horizontal line) lSimple cells (respond to the shape and size of lights) lComplex cells (respond most vigorously to the movement of light in one direction) lHypercomplex cells (respond only to a line of the correct length and orientation that moves in the proper direction) lField detector cell (cell that detects lines and edges)

Vision: the sense of sight

ØHumans derive more information through sight than through any other sense ØNecessary to understand how the physical input (light) is translated into the language of the brain ØVisible light exists as a small band of energy contained within the electromagnetic spectrum, the entire spectrum of waves initiated by the movement of charged particles

Electromagnetic spectrum

ØIncludes gamma rays, x-rays, ultraviolet rays, visible light, infrared rays, radar, broadcast bands, and AC currents ØVisible light is a very small portion of that spectrum The eye is a highly evolved sensory receptor that has some really cool components. The eye is a concentration of cells that are sensitive to light energy. Your eye isn't actually seeing color, but rather pulses of electromagnetic energy, which our eye then translates into experiencing color. The longer wavelengths include AC circuits, radio waves, and infrared rays. The shorter wavelengths include: visible light, UV rays, X-rays, and gamma rays. The visible light spectrum refers to only the part of the electromagnetic spectrum that humans can see. It ranges from 400 nanometers (violet) to 700 nanometers (red). Visible light is a very small portion of that spectrum and may come directly from a source or may be reflected from an object. Light affects about 30 brain areas that are involved in sensation and perception. The eye is highly specialized by species such that animals are most adept at seeing those wavelengths that are most important to their survival. Humans have developed very sensitive acuity to the spectrum of wavelengths that is visible to us but other animals see other wavelengths. Bees don't see red, but they do see ultraviolet rays and blue-violet light. This allows it to be able to better see pollen, their food source. The pit viper and rattlesnakes can see infrared rays (which humans are unable to see), which allow it to see better in the dark than its prey. Thus, it is more effective at hunting at night than its prey is at defending itself. And dogs don't see all the colors that we see, but they do have better peripheral vision (though worse close-up vision). name ROY G. BIV - red, orange, yellow, green, blue, indigo, violet. Visible spectrum is a subset of the electromagnetic spectrum, ultraviolent to infrared

Transduction

ØIs the process by which the nervous system converts an external stimulus, like light or sound, into electrical signals within neurons Ø ØSense receptor: specialized cell responsible for converting external stimuli into neural activity for a specific sensory system Ø ØSensory adaptation: activation is greatest when a stimulus is first detected Our sensory systems are designed to detect novelty, contrast, and change - not sameness. After constant exposure to a stimulus, sensation fades. This decline in sensitivity is known as sensory adaptation. After a while, you simply get used to the new contact lenses in your eyes, the new watchband on your wrist, the noise level at work, or the coldness of winter. To those of you sensitive to the smells that often pervade the hallways of apartment buildings (or dorms), it is comforting to know that people also adjust to chronic odors. By adapting to a repeated stimulus, you are free to detect important changes in the environment. There was a commercial on TV a couple of years ago about being "nose blind". What they meant is that often we get used to the smell of our houses or our cars and we don't notice that there is an odour(e.g., pets, smoke, spices, etc.); other people, however, do notice them right away when they enter and they are strong at first. If you move near an airport or train tracks, the noise will be annoying in the beginning; however, in time you may not even notice them anymore. I love trains and used to live near the tracks. The whistle never bothered me but it bothered my roommate so much so that we had to move. My roommate worked out of town a lot and wasn't there enough to habituate to the sound. Transduction: convert external energies into something that the nervous system can understand (action potential), sense receptors transduce a specific stimulus- special cells at the back of the eye transduce light, cells in the spiral organ in the cell transduce sound, odd looking enzymes attached to axons in the deep layer of the skin transduce pressure, receptor cells lining the inside of the nose transduce airborne odorants and taste buds transduce chemicals containing flavour

Visual Transduction

ØLight, a form of electromagnetic energy, is delivered to visual receptors Ø ØLight is classified by two main physical properties Ø lWavelength (ranging from about 400 to 700 nanometres "nm"); changes experienced as changes in hue l lIntensity or amount of light falling on an object; changes are generally experienced as increases or decreases in brightness The length of a light wave determines its hue, or perceived color. To the human eye, white light is made up of all visible wavelengths combined. Short wavelengths look bluish, medium wavelengths look greenish, and long wavelengths look reddish. A second property of light is its intensity, or amplitude, as measured by the height of the peaks in the wave. As wavelength determines color, amplitude determines brightness. The higher the amplitude, the brighter the light appears to be. Hue- colour of light, primary colours of light- red, green, blue, the mixing of these three colours (additive colour mixing) can produce any colour, equal amounts of each colour= white light, but this differs from mixing pigments in paint (subtractive colour mixing), printer ink- yellow, cyan and magenta- mixing creates a dark color because each pigment absorbs different wavelengths so when they are combined- they absorb most of the wavelength leaving little or no colour

Lateral Geniculate Nucleus

ØOne of the major visual projection areas of the visual system Ø In the electrochemical basis of perception, researchers are working on a visual prothesis (a device to help people who are blind to see - it bypasses the eyes and directly stimulates the visual cortex lateral geniculate nucleus This is one of the major visual projection areas of visual system; it then goes to the visual cortex or striate cortex of the occipital lobe (most important area of occipital lobe as this is where perception occurs).

Pressure and tickling

ØPain: is a perceptual experience with particular negative qualities; physical and psychological Ø ØGate Control Model: idea that pain is blocked or gated from consciousness by neural mechanisms in the spinal cord Ø ØPain insensitivity Ø ØPhantom pain There are specialized receptors for each of skins senses - touch, pain and temperature; they vary in shape, size, number and distribution (more cold receptors than hot; more pain receptors behind the knee than on the top of the nose). In the most sensitive areas of the hands, there are as many as 1300 receptors per square cm; skin sense receptors appear to interact with one another. It is interesting that what is perceived as pressure can become pain; some people are far more sensitive to pressure in some areas than others. Women are better than men with some pain stimuli. For you, what is the area of the body where pain is the worst? Tickle Tickling is partly physical but mostly psychological; people can't tickle themselves (surprise).It is very interesting (and I usually did this in class) that if you approach someone with "tickle fingers" they start to move away and giggle - you don't even have to ever touch them.They know what it feels like and start giggling ahead of time.However, it can "go wrong". Sometimes the brain locates sensations that cannot possibly be present-phantom pain- amputees experience vivid sensation from the missing limb, irritation of the nerves tricks the brain to believing that the sensation is real, Joel Cats and Ronald Melzac- 1990 studied amputees with phantom pain, not a recollection of pain- actually experienced in the limb, disappears with prosthetics

Sound

ØPsychological experience that occurs when changes in air pressure take place at the receptive organ for hearing; the resulting tones, or sounds, vary in frequency and amplitude Ø ØFrequency: in sound waves, a measure of the # of times a complete change in air pressure occurs per unit of time, expressed in hertz (Hz) or cycles per second Ø lDetermines the pitch, or tone, of a sound Sound - audio A tuning fork, the reed of an instrument or a person's vocal cords result in vibrations that cause sound waves (feel the waves in front of speakers) Sound: psychological experience that occurs when changes in air pressure take place at the receptive organ for hearing; the resulting tones, or sounds, vary in frequency and amplitude Frequency: in sound waves, a measure of the # of times a complete change in air pressure occurs per unit of time, expressed in hertz (Hz) or cycles per second - determines the pitch, or tone, of a sound Sound is vibration, a kind of mechanical energy travelling through a medium (air), the disturbances created by vibrational molecules of air produces sound waves- can travel through any gas, liquid or solid but we hear them best when they travel through air. Perfectly empty space (vacuum) there cannot be sound because there are not any airborne molecules to vibrate- does a falling tree in a forest make a sound? Yes there are air molecules in the forest, even if no one is there to hear it Frequency is the number of sound waves per second, the hertz is the technical measure of cycles per second, frequency is related to the pitch that we perceive- higher the frequency (hertz) the higher the perceived pitch, humans can detect sound from 20-20 000 Hz, most common sounds are in the lower frequencies, piano can play widest range of frequencies- 27.5 Hz-41086 Hz, soprano voice has a range of 250 -1100 Hz

absolute threshold

ØThe minimum level of stimulation necessary to define the transition from what is undetectable to that which is detectable 50% of the time Ø ØDifference threshold: the amount of change necessary for an observer to report 50% of the time that a level of stimulation (say mass) has changed or is different from another value (has gotten heavier or lighter) Absolute thresholds demonstrate how sensitive our sensor systems are. On a clear night, our visual systems can detect a single candle from 50 kilometres away; we can detect a smell from as few as 50 airborne odorant molecules (Menini et al., 1995). Absolute Threshold- how strong does a stimulus have to be for us to recognize it- research is going into it, lower the threshold, greater the sensitivity, general limits of human sensitivity for the five major senses can be estimated, hearing the tick of a watch at approximately 6 meters, taste a single teaspoon of sugar in approximately 7.5 L of water, smell- one drop of perfume diluted in an apartment, touch - wing of a fly falling on your cheek from a distance of 1 cm

Just Noticeable Difference

ØThe smallest change in the intensity of a stimulus that we can detect Ø ØRelevant to our ability to distinguish a stronger from a weaker stimulus Ø ØWeber's Law: there is a constant proporational relationship between the JND and ongoing stimulus intensity JND is 2% for brightness, 10% for loudness, and 20% for the taste of salt. As we get older, our taste buds aren't as efficient so many people put way too much salt on their food in order to just taste it. JND: soft noise from a slightly louder noise, music through and MP3- so low that we can't hear it and then just loud so that we can hear it, the stronger the stimulus, the bigger the change needed for the change in stimulus intensity to be noticeable, notice a difference between a brightly illuminated kitchen and the amount of light needed to illuminate dark room

Middle and inner ear

ØTiny bones (ossicles) known as the hammer, anvil and stirrup help convert the large forces striking the eardrum into a small, concentrated force Ø ØTwo small muscles are attached to the ossicles Ø ØMiddle ear bones stimulate the basilar membrane (runs down the middle of the cochlea - spiral tube in the inner ear) Ø ØIn cochlea, sound waves of different frequencies stimulate different areas of the basilar membrane; stimulate hair cells; then to brain's auditory nervous system (inner ear)- auditory nerve to midbrain to auditory cortex respond to displacement as small as 100 picometres or trillions of a metre. Resting on the basilar membrane is the Organ of Corti, which contains about 16000 tiny hair cells that are the actual sound receptors. The tips of the hair cells are attached to the tectorial membrane that overhangs the basilar membrane along the entire length of the cochlea. The hair cells synapse with the neurons of the auditory nerve which, in turn, sends impulses via an auditory relay station in the thalamus to the auditory cortex, which is located in the temporal lobe.

Sensory Integration Disorder

Øformerly known as "sensory integration dysfunction") is a condition that exists when sensory signals don't get organized into appropriate responses. Ø Ø A person with SPD finds it difficult to process and act upon information received through the senses, which creates challenges in performing countless everyday tasks. Ø ØMotor clumsiness, behavioral problems, anxiety, depression, school failure, and other impacts may result if the disorder is not treated effectively. -Pioneering occupational therapist and neuroscientist A. Jean Ayres, PhD, likened SPD to a neurological "traffic jam" that prevents certain parts of the brain from receiving the information needed to interpret sensory information correctly. - -These folks may get overwhelmed with the amount of stimuli encountered and actually "shut down" in order to stay sane; they receive too much too fast.

Somatic nervous system

•Controls voluntary muscles and conveys sensory information to the CNS and sends motor messages to muscles •Sensory neurons: transmit messages from sense organs to the CNS (brain and spinal cord), also known as afferent neurons •Motor neurons: transmit messages from the CNS to organs, muscles, and glands; also known as efferent neurons •Inter-neurons: neurons within the CNS that internally communicate and intervene between the sensory and motor neurons regulates the actions of the body's skeletal muscles (movement of fingers when you are texting or typing on the computer keyboard) Sensory neurons transmit messages from ears, eyes and other sensory receptors, motor neurons send signals to muscles for voluntary movement, sensory axons look like a rope when combined to make nerves, motor neurons also combine to make nerves- inside brain and spinal cord are called tracts, visual tracts, motor neurons are moving eyes, sense and respond to environment

Neurotransmitters and psychoactive drug

•Drugs that interact with neurotransmitter systems are called psychoactive •Opiates such as codeine and morphine function as agonists (they increase receptor site activity) •Antagonists, that decrease receptor site activity, such as medications for serotonin How do neurotransmitters communicate? Neurotransmitters bind to receptor sites on dendrites in similar way to how a key fits a lock (different keys have distinct three-dimensional shapes - different neurotransmitters have distinguishing three-dimensional characteristics) thus influencing the firing of the receiving cell. Agonists mimic or enhance the action of neurotransmitters both the poison of the black widow spider and nicotine in cigarettes have a molecular structure similar enough to acetylcholine (ACh) that increase heart rate amphetamines produces a similar excitatory effect by mimicking norephinephrine Antagonists work by opposing or blocking neurotransmitters snake venom and some poisons (e.g., curare used by SA hunters) act as antagonists to Ach (Acetylcholine) because ACh is vital to muscle action, blocking it paralyzes muscles, including those involved in breathing

Glutamate and GABA (gamma aminobutyric acid )

•Glutamate excites while GABA inhibits • •Glutamate related to enhanced learning and memory; may contribute to schizophrenia and other mental disorders • •GABA inhibits so most anti-anxiety medications bind to GABA receptors; critical roles in learning, memory and sleep GABA (gamma aminobutyric acid): neural inhibition in the CNS; tranquilizing drugs, like Valium, increase GABA's inhibitory effects thereby decreasing anxiety, alcohol abuse, seizure disorders and sleep disorders

Monoamines

•Norepinephrine, dopamine, and serotonin are the monoamine neurotransmitters (called "monoamines" because they contain only one amino acid, the building blocks of proteins) Dopamine (DA): involved in movement, thought processes, attention, memory, learning, emotion (feelings of reward and pleasure); excess dopamine levels are associated with Schizophrenia-due to overactivity in certain dopamine systems.; too little dopamine is associated with Parkinson's Disease-- dopamine creator cells degenerate and die= loss of voluntary motor control- aldopa- to increase amount of dopamine in the brain Motivation, voluntary motor control and control of thought processes Anti-psychotics block dopamine and prevent it from having an effect, associated with the motivation of drugs of abuse ; it also plays a role in addiction and the reward system as it affects the pleasure centre of the brain. Serotonin: substance derived from the amino acid tryptophan (component in many foods); motivation and mood (anxiety and depression), sleep regulation, appetite (especially carbs), sensory perception, temperature regulation, sexual behaviour, pain suppression, and impulsivity; low levels (abnormal depression of serotonin) associated with depression (antidepressants affects levels of serotonin), Anti-psychotic drugs increase serotonin activity in several ways- Prozac (SSRIs) block the reuptake of serotonin from the synaptic space, allowing the serotonin to remain active and exert mood altering affects, may inhibit enzymes that act on serotonin by breaking it down into simpler chemicals- prolong serotonin activity at the synapse Norephinephrine (NE) or Noradrenaline: arousal reactions and acts on several parts of the brain (increased heart rate, increased respiration, increased sweating and dilation of the pupils of the eyes), learning, memory, dreaming, emotion, waking from sleep, eating, alertness, wakefulness, reactions to stress, sexual activity; low levels of NE associated with depression; high levels with agitated, manic states

Acetylcholine

•Roles in arousal, selective attention, REM sleep, memory, emotion, muscle action •Implicated in Alzheimer's Disease (Aricept boosts levels of Acetylcholine) •Used in insecticides Receptors appear in many parts of the brain and throughout the body (many functions); effect typically EXCITATORY (excitation of the skeletal muscles...muscles that allow you to move); cognitive functioning, memory, REM sleep, emotion; suspected role in Alzheimer's Disease- under production, neurodegenerative disease with profound memory impairment, synapse of muscles, drugs that block Ach can prevent muscle activation= paralysis- botulism (improperly canned food)- blocks Ach release from axonal terminal= paralysis of muscles (fatal- respiratory system), black widow spider bite- too much Ach= violent muscle contractions, convulsions

Neural bases of behaviour

•What is a neuron? •cell of the nervous system responsible for receiving and transmitting electrochemical information; three types: •Sensory neurons: transmit messages from sense organs to the CNS (brain and spinal cord), also known as afferent neurons •Motor neurons: transmit messages from the CNS to organs, muscles, and glands; also known as efferent neurons •Inter-neurons: neurons within the CNS that internally communicate and intervene between the sensory and motor neurons each neuron is a tiny information processing system with thousands of connections for receiving and sending signals to other neurons there are approximately one trillion neurons in each human body It is not uncommon for 1 neuron to receive input on 20,000 to 30,000 synapses They are highly specialized and amitotic (if a neuron is destroyed it cannot be replaced because neurons do not go through mitosis - cell division and replication) Sensory/Afferent Neurons are highly specialized neurons that act to encode sensory information (e.g., photoreceptors of eye transform variations of light intensity into electrical and chemical signals that can be read by other nerve cells) Interneurons: receive signals from and send signals to other neurons; process information in many different ways and constitute the bulk of the human nervous system Motor/Efferent Neurons: send signals to the muscles and glands of the body; directly governing the behaviour of the organism There are also two categories of neurons depending on their length: Principal neurons: transmit information over long distances from one brain region to another Local circuit neurons: lack long axons (exert all their effects in the local region of their cell bodies and dendrites) NEURONS ARE NOT TO BE CONFUSED WITH NERVES; Nerves are large bundles of axons that carry impulses to and from the brain and spinal cord. Under a microscope nerves look something like telephone cables, with their bundles of wires, all wrapped in a tough protective membrane.

Cell body (soma)

•accepts incoming messages; if enough stimulation the soma will pass the message on to the axon •Contains nucleus where proteins are manufactured; damage to this part of the neuron is fatal The Cell body receives messages from the dendrites. This is the part of the neuron that contains the cell nucleus, as well as other structures that help the neuron carry out its functions; it provides life processes of the cell. The nucleus ("nut") is round or oval and is enclosed by the nuclear membrane. The nucleolus and the chromosomes reside here.

Limbic system

•an interconnected group of structures involved in emotions, memory, motivation, and brain disorders (e.g., epilepsy) •hippocampus and amygdala (a set of nuclei connected to the hippocampus) -involved in emotional control and in the formation of emotional memories - stimulation of the amygdala in animals produces attack responses (i.e., rabies leads to the destruction of the amygdala) - learning of fear and other emotional responses - possible "pleasure centres" in animals Damage to this area may have a calming effect on otherwise mean-spirited individuals; damage to some areas results in an inability to recognize emotional content of facial expressions, especially fear. It may play a role in people's acquisitions and use of knowledge related to threat and danger. However, some types of new memories can still be formed after damage to the hippocampus (aquiring new skills); if you had this damage you could still be able to learn some new tasks but you would not be able to remember doing them. Behaviors to satisfy motivational and emotional urges, memory, organize instinctive behaviours in animals- goal directed, if injured- unable to carry out sequence to satisfy needs, small distraction would make you forget what you set out to do, hippocampus- forming and storing memories- damage= severe memory loss of recent events, cannot transmit short term to long term memory, amygdala- organizes emotional response patterns-aggression and fear, can electrically stimulate areas to provoke snarling and be aggressive or fear, key part of larger control system for emotional regulation that also involves other brain structures Limbic System Video Limbic- border between cerebral cortex and diencephalon, emotion, no censuses on structures that are included, amygdala- almond shaped nuclei found in the temporal lobe, involved in fearful and anxious emotions, hippocampus- next to amygdala, memory, parahippocampal gyrus- surrounds the hippocampus and also plays a role in memory, cingulate cortex (gyrus)- just above corpus callusom, involed in various aspects of emotions and memory, septal nuclei- connections with other limbic structures and are thought to be especially used for pleasure, reward and reinforcement, mammillary bodies- memory, connection to amygdala and hippocampus, fornix- fiber bundle that carries information from hippocampus to the mammillary bodies and then onto the thalamus, hypothalamus- controls hormone release- anterior pituitary , gathers info about body states to maintain homeostasis

Cortex

•brain has two major portions (youngest parts of our brain) •exterior covering, two millimeters thick and consists of six thin layers of nerve cells •most of cerebral cortex is the neocortex •convoluted or furrowed (gyri and fissures) to create more surface area in a small space •intimately involved in thought and reasoning The cerebrum is divided into two almost symmetrical halves, the cerebral hemispheres connected by a thick mass of nerve fibres (corpus callosum). It is convoluted or furrowed (gyri, sulci, and fissures) to create more surface area in a small space. Neuroscientists have mapped each hemisphere using two important landmarks; one groove, the central sulcus, divides each hemisphere vertically, and a second similar groove, lateral fissure, divides each hemisphere horizontally (these divisions help define four areas, or brain lobes (frontal, temporal, parietal, occipital lobes). It is intimately involved in thought and reasoning.

Neurotransmitters

•chemicals released by neurons that affect other neurons; some exciteand some inhibit •produced from materials in the blood (originally derived from foods) •some regulate actions of glands and muscles •some promote sleep or stimulate mental and physical alertness •some affect learning and memory •some affect motivation, emotions, and psychological disorders (e.g., schizophrenia and depression) Epinephrine (or adrenaline): emotional arousal, memory storage, and metabolism of glucose necessary for energy release Neuropeptides are chains of amino acids that act much like neurotransmitters (pseudotransmitters); examples are endorphins Endorphins (endogenous opioid peptides) Endorphins produce effects similar to those of opiod-based drugs such as morphine by reducing pain by inhibiting synaptic transmissions and promoting pleasure); runner's high mimicked by morphine. These were discovered in early 1970s (Pert and Snyder). They are involved with mood, pain, memory, and learning. Reduce pain and increase feelings of wellbeing, able to still function after injury-endorphins act as analgesics Neuromodulators: chemical substances that function to increase or decrease the sensitivity of widely distributed neurons to the specific effects of other neurotransmitters; a neuropeptide released into the bloodstream affects not only a single cell's immediate ion transfer but also whole classes, groups, or networks of cells (such as within the limbic system emotional responses), more wide spread and generalized influence on synaptic transmissions- increase or decrease (modulate) the sensitivity to neurotransmitters, eating, sleep and stress Most have excitatory or inhibitory effect on specific neurons that have receptors- neurotransmitters create a more specific response ** studying neurotransmitters not only helps us understand medical/mental problems but also explains how poisons, mind-altering drugs (e.g., nicotine, alcohol, caffeine, cocaine) affect the brain most of these substances either replace, decrease, or enhance the amount of neurotransmitters at the synapse

Frontal lobe

•concerned with higher order functions such as memory; monitoring, organizing, and directing thought processes; planning and paying attention •specialized speech and language production area (Broca's area) •primary motor cortex (Walter Penfield, 1958) •right frontal lobe's role in appreciating humour (Shammi and Stuss, 1999) and self-awareness (Stuss, 1991) •damage: personality, impulsivity, planning, initiating Broca's area in the frontal lobe is necessary for normal speech production. The neural circuits in and around Broca's area are important for the ability to perform the sequences of fine-motor movements needs to speak, and are involved in the abilities to use grammar and find the correct word (Saffran et al., 1980). Its discoverer, Paul Broca, found that damage to this frontal area left patients wit the ability to comprehend (understand) speech but not to express themselves with words or sentences. Wernicke's area in the temporal lobe and Broca's area usually work together when you are conversing with another person. They allow you to understand what the other person is saying and to express your own thoughts

Hindbrain (Rhombencephalon)

•consists of the medulla, the reticular formation, the pons and the cerebellum The Hindbrain consists of the medulla, the reticular formation, the pons and the cerebellum. Medulla: controls heartbeat and breathing and through which many afferent and efferent signals pass, first structure after leaving the spinal cord, developed at birth, 3.8 cm, automatic functions, damage- death or life support, suppression can occur with high levels of alcohol intoxication- heart or resp failure, two way tracts for all sensory and motor, cross over, left side receives sensory input from and exerts motor control over the right side, right side controls left side- why this crossover occurs is one of the unsolved mysteries Reticular Formation (within the Medulla): controls a person's state of arousal; normal function controls waking and sleeping but damage can result in coma and death. The reticular formation is damaged quite easily in whiplash when the head snaps forward and backwards rapidly. It extends into and through the pons and the midbrain, with projections toward the cortex. Pons: provides the link with the midbrain; it affects sleep and dreaming, just above medulla, carries nerve impulses between higher and lower levels of the nervous system, cluster of neurons to regulate sleep- dreaming, muscle and glands of face and neck, resps, damage= death The Cerebellum ("little brain") influences balance, coordination, and movement, including single joint actions (e.g., flexing of elbow or knee). It is 10% of total volume of brain but contains more than ½ of the total neurons. It allows you to walk a straight line, type accurately, coordinate dancing movements, and hit a golf ball. Alcohol impairs the ability of this area of the brain and that is why you are asked "to walk a straight line". Attached at rear of the brainstem, directly above the pons, wrinkled cortex has grey matter, muscle movement coordination, learning and memory, specific motor movement timing and coordination-complex, rapidly changing movements that require exquisite timing- ballet dancer, diver, cats are well developed- graceful movements, easily disrupted with alcohol-coordination difficulties, damage= severe motor disturbances- jerky, uncoordinated movements, inability to preform habitual movements- walking

Nodes of Ranvier

•gaps (approximately 1 micrometer wide) formed between myelin sheath cells along the axons which helps the conduction of nerve impulses •Action potentials occur at these gaps in myelinated neurons The depolarization spreads down the axon to the next node in a process called salutatory conduction (which comes from the Latin "to leap or to dance". This confers two advantages. The first is economic in that myelinated axons expend much less energy to maintain their sodium balance as the action potential only occurs in the gaps. The second advantage is speed.

How fast does a neural impulse travel?

•more slowly than electricity through a wire (97% speed of light - 300 million metres per second) •10 metres per second (non-myelinated) •100 metres per second (myelinated) [This rapid rate of conduction is called saltatory conduction.] Myelinated axons are rare in the autonomic nervous system (ANS) Travel speed is 10 metres per second in non-myelinated neurons but is 100 metres per second in myelinated neurons. [This rapid rate of conduction is called saltatory conduction.] - Myelinated axons are rare in the autonomic nervous system (ANS). -Invertebrates do not have myelinated sheaths

Glial cells

•neurons are held in place and supported by glial cells that surround neurons, perform cleanup tasks, insulate one neuron from another so that their neural messages are not scrambled (communication function) Neurons constitute only about half of the volume of the CNS. The rest consists of a variety of supporting cells. Because neurons have a very high rate of metabolism but no means of storing nutrients, they must constantly be supplied with nutrients and oxygen or they will quickly die. Thus the role played by the cells that support and protect neurons is very important to our existence. Glial cells ("glue") [glia/neuroglia] These are the most important supporting cells of the central nervous system. There are 10 times more glial cells than there are neurons; they surround neurons and hold them in place, perform cleanup tasks by destroying and removing the carcasses of neurons that are killed by disease or injury, and insulate one neuron from another so that their neural messages are not scrambled. There are several types of glial cells, each of which plays a special role in the CNS. The three most important types are astrocytes, oligodendrocytes, and microglia. Astrocyte means "star cell" and this name describes the shape of these cells; they provide physical support to neurons and clean up debris within the brain. They also are involved in providing nourishment to neurons. Oligodendrocytes' principal function is to provide support to axons and to produce the myelin sheath, which insulates most axons from one another. Myelin, which is 80% lipid and 20 percent protein, is produced by the oligodendrocytes in the form of a tube surrounding the axon. This tube does not form a continuous sheath; rather it consists of a series of segments, each approximately 1 mm long, with a small portion of uncoated axon between the segments (the nodes of Ranvier - named after its discoverer). The myelinated axon, then, resembles a string of elongated beads - very elongated as their length is approximately 80 times their width). Microglia are the smallest of the glial cells. They act as phagocytes, engulfing and breaking down dead and dying neurons. However, in addition, they serve as one of the representatives of the immune system in the brain, protecting the brain from invading microorganisms. They are primarily responsible for the inflammatory reaction in response to brain damage. Manufacture/ transport nutrients, form the myelin sheath, absorb toxins and waste materials, during neonatal development- glial cells send out long fibers that guide the new neurons to their eventual place, outnumber neurons 10:1, protect brain from toxins- circulation, blood brain barrier- walls of blood vessels have smaller gaps, and are covered by specialized glial cells, modulate communication