Psych: Chapters 1-6 for Exam 1

Validity

"In psychology, tests are usually judged according to their validity and their reliability (if the test produces similar results each time the test is taken). Tests that are valid are also reliable. However a test might be reliable without it being valid. For example, let's say you go to class and your teacher says that he or she has learned that the weight of your head determines the likelihood of you getting cancer. So, each day at the beginning of class the teacher weighs everybody's head on a scale. This continues for one week. Across each day of the week, the weight of your head is going to remain approximately the same; thus we can conclude that the test is reliable. However, is this test valid; does it measure what it is intended to measure (that the weight of your head predicts the likelihood of you getting cancer)? The answer is....NO! So, although the test is reliable, it is not necessarily valid (it does NOT measure what it was designed to measure)."

Gestalt Psychology

"The whole is greater than the sum of its parts" school of psychology founded in the 20th century that provided the foundation for the modern study of perception. Gestalt theory emphasizes that the whole of anything is greater than its parts. That is, the attributes of the whole are not deducible from analysis of the parts in isolation. The word Gestalt is used in modern German to mean the way a thing has been "placed," or "put together." There is no exact equivalent in English. "Form" and "shape" are the usual translations; in psychology the word is often interpreted as "pattern" or "configuration."

5 perspectives of psychology

--Biological Approach Biopsychologists look at how your nervous system, hormones and genetic makeup affect your behavior. Biological psychologists explore the connection between your mental states and your brain, nerves and hormones to explore how your thoughts, moods and actions are shaped. So what does that mean? It means that for the biological approach, you are the sum of your parts. You think the way you do because of the way your brain is built and because of your body's needs. All of your choices are based on your physical body. The biological approach attempts to understand the healthy brain, but it also examines the mind and body to figure out how disorders like schizophrenia develop from genetic roots. --Psychodynamic Approach The psychodynamic approach was promoted by Sigmund Freud, who believed that many of our impulses are driven by sex. Psychologists in this school of thought believe that unconscious drives and experiences from early childhood are at the root of your behaviors and that conflict arises when societal restrictions are placed on these urges. There are a lot of jokes about Freud and his now mostly outdated theories. But have you ever thought that something about who you are today comes from your experiences as a child? Say, you blame your smoking habit on an oral fixation that stems from being weaned from breastfeeding too early as a baby. Well, that also comes from Freud's theories, and it was an idea that revolutionized how we see ourselves. --Behavioral Approach Behavioral psychologists believe that external environmental stimuli influence your behavior and that you can be trained to act a certain way. Behaviorists like B.F. Skinner don't believe in free will. They believe that you learn through a system of reinforcements and punishment. The behavioral approach is really effective when you don't care what someone thinks, as long as you get the desired behavior. The influence of these theories affects us every day and throughout our lives, impacting everything from why we follow the rules of the road when driving to how advertising companies build campaigns to get us to buy their products. --Cognitive Approach In contrast to behaviorists, cognitive psychologists believe that your behavior is determined by your expectations and emotions. Cognitive psychologist Jean Piaget would argue that you remember things based on what you already know. You also solve problems based on your memory of past experiences. So, with this approach, we turn away from people as machines without free will and delve back into thoughts and feelings. How you act is based upon internal processes, and there is much more stress upon individuals. From a cognitive perspective, your expectations of an upcoming party will affect how you feel and act while you're there and will color your memory of the night after you return home. --Humanistic Approach Humanistic psychologists believe that you're essentially good and that you're motivated to realize your full potential. Psychologists from this camp focus on how you can feel good about yourself by fulfilling your needs and goals. The prominent humanistic psychologist Carl Rogers called his patients 'clients' and offered a supportive environment in which clients could gain insight into their own feelings. In contrast to the behavioral approach, the humanistic approach works on individual empowerment. Whether you are right or not, in a larger sense, you are motivated to be the best person you can be. All your choices come from trying to improve your life. So, if you're trying to cut back on your nightly wine consumption, a humanistic therapist would be encouraging and supportive but won't directly advise you to quit or try to analyze why you drink in the first place.

What is psychology?

-The scientific study of behavior and mental processes. -Psychology is the scientific study of the mind and behavior. Psychology is a multifaceted discipline and includes many sub-fields of study such areas as human development, sports, health, clinical, social behavior and cognitive processes.

What are the three possible explanations for a correlation?

1. The correlation is a coincidence. 2. One event causes the other. 3. The two events are both caused by some third event.

3 major properties of sound

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What do we dream?

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Population

A group of individuals of the same species occupying a particular geographic area. Populations may be relatively small and closed, as on an island or in a valley, or they may be more diffuse and without a clear boundary between them and a neighboring population of the same species.

Theory

A hypothesis that has been tested with a significant amount of data and is considered a plausible or scientifically acceptable general principle or body of principles offered to explain a particular phenomena

Mirror neurons

A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behavior of the other, as though the observer were itself acting. ... The function of the mirror system in humans is a subject of much speculation.

Neurotransmitters

A neurotransmitter is a chemical messenger that carries, boosts, and modulates signals between neurons and other cells in the body. In most cases, a neurotransmitter is released from the axon terminal after an action potential has reached the synapse. he neurotransmitter then crosses the synaptic gap to reach the receptor site of the other cell or neuron. Then, in a process known as reuptake, the neurotransmitter attaches to the receptor site and is reabsorbed by the neuron. Neurotransmitters play a major role in everyday life and functioning. Scientists do not yet know exactly how many neurotransmitters exist, but more than 100 chemical messengers have been identified. When neurotransmitters are affected by disease or drugs, there can be a number of different adverse effects on the body. Diseases such as Alzheimer's and Parkinson's are associated with deficits in certain neurotransmitters.

Stroop Test

A test used to measure a person's sustained attention-eg, for word reading and color naming-with/without interference. The Stroop effect is a phenomenon in which you must say the color of a word but not the name of the word. ... The Stroop effect refers to a phenomenon in which it is easier to say the color of a word if it matches the semantic meaning of the word.

Hypothesis

A testable prediction, often implied by a theory or a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

Dependent Variable

A variable whose value depends on that of another. Not manipulated like independent variable

Greenwald et al (1991) experiment on subliminal self-help tapes

Abstract Three replications of a double-blind experiment tested subliminal audiotape products that were claimed to improve memory or to increase self-esteem. Conditions of use adhered to manufacturers' recommendations, and subjects (N = 237) were limited to persons who desired the effects offered by the tapes. Actual content and labeled content of tapes were independently varied, so that some subjects who believed they were using memory tapes were actually using self-esteem tapes, and vice versa. After a month of use, neither the memory nor the self-esteem tapes produced their claimed effects. Nevertheless, a general improvement for all subjects in both memory and self-esteem (a nonspecific placebo effect) was observed, and more than a third of the subjects had the illusion of improvement specific to the domain named on the tape's label.

Functionalism

An American psychologist named William James (1842-1910) developed an approach which came to be known as functionalism. He argued that the mind is constantly changing and it is pointless to look for the building blocks of experience. Instead, focus should be on how and why an organism does something. It was suggested that psychologists should look for the underlying cause of behavior and the mental processes involved. This emphasis on the causes and consequences of behavior has influenced contemporary psychology.

Axon

An axon or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma. Each neuron has a nerve body, dendrites, and axons, all of which are used to send information throughout your body. The axon carries signals (electric voltages) between the dendrites (the neuron's input sites) and the terminal buttons (the neuron's output sites that are at the very end of the axon). The signal always travels in the same direction - the signal comes into the neuron through the dendrites, through the cell body (soma), to the axon, and then out the terminal buttons to the dendrites of the next neuron. In this way information travels all around your body by going from neuron to neuron.

Monocular and Binocular depth cues

Binocular depth cues Stereopsis--when both the left eye and the right eye view an object at a slightly different angle. Caused by horizontal separation of both eyes. Convergence--is when the eyes fixate on an object that it far away. This convergence stretches the extraocular muscles in the eye causing kinesthetic sensations which help in depth perception. Shadow Stereopsis--are retinal images with no parallel disparity, but with different shadows that are fused stereoscopically, giving depth perception to the scene Monocular depth cues Relative Size--If two objects are roughly the same size, the object that looks the largest will be judged as being the closest to the observer. Texture Gradient--When you are looking at an object that extends into the distance, such as a grassy field, the texture becomes less and less apparent the farther it goes into the distance. Motion Parallax--As you are moving, objects that are closer seem to zoom by faster than do objects in the distance. When you are riding in a car for example, the nearby telephone poles rush by much faster than the trees in the distance. Aerial Perspective--Objects that are farther away seem to be blurred or slightly hazy due to atmosphere. Linear Perspective--Parallel lines appear to meet as they travel into the distance. For example, the outer edges of a road seem to grow closer and closer until they appear to meet. The closer together the two lines are, the greater the distance will seem.

Cherry (1953) study

Cherry is best known for his work on the "cocktail party effect," the human ability to follow a single conversation while many other conversations are proceeding at the same time. This is a relatively easy task for human beings in a normal live environment. However, the mechanism by which we process the incoming sounds and selectively attend to the appropriate speaker is still not clearly understood and it remains a very difficult problem for computers. "Other researchers have demonstrated the 'cocktail party effect' (Cherry, 1953) under experimental conditions and have discovered occasions when information heard in the unattended ear 'broke through' to interfere with information participants are paying attention to in the other ear. This implies some analysis of meaning of stimuli must have occurred prior to the selection of channels. In Broadbent's model the filter is based solely on sensory analysis of the physical characteristics of the stimuli."

Endocrine system

Communication from the brain is sent to the rest of the body by the endocrine system as well as by the nervous system. The endocrine system is a series of glands throughout the body that secrete chemicals (hormones) into the bloodstream; hormones, in turn, affect body functions.

Know about these cells in the retina: - rods and cones

Cones are receptor cells that help us see fine details of things and tend to help us see in situations where there is light or daylight. The majority of cones are in the center of the retina (we have approximately 6 million cones in each eye). When you squint to try to read or see something more clearly, what you are actually doing is focusing the image on this grouping of the cones in order to see the fine details. Cones also help us with color perception. The rods are the receptors in the eye which detect movement. Rods are also used in night vision.

Correlation Types of correlations

Correlation means association - more precisely it is a measure of the extent to which two variables are related. If an increase in one variable tends to be associated with an increase in the other then this is known as a positive correlation. An example would be height and weight. Taller people tend to be heavier. If an increase in one variable tends to be associated with a decrease in the other then this is known as a negative correlation. An example would be height above sea level and temperature. As you climb the mountain (increase in height) it gets colder (decrease in temperature). When there is no relationship between two variables this is known as a zero correlation. For example their is no relationship between the amount of tea drunk and level of intelligence.

What is 'dark adaptation' and 'light adaptation'?

Dark Adaptation is the process by which our eyes adjust to darkness after being exposed to light. For example, when we move from a bright, sunny area outside to a relatively dark room inside, it is difficult to see at first. But gradually our eyes recover and become more sensitive to the dim light indoors. Dark adaptation is made possible by the dilation of our pupils and changes in the rods and cones of our retinas. Rods detect form and motion, and cones detect color. So in darkness, our rods kick into high gear while the cones take a backseat. Light adaptation is the adjustment of the eyes when we move from darkness into an area that is illuminated. During this adjustment period the sensitivity of the retina decreases. The cones of the eyes begin reacting to the brightness of the light and become more active than the rods of the eye. This increases the accuracy of vision and the sensation of color. You know how when you leave a dark room for the bright light of a sunny day there are spots and color distortion that eventually fade away? This is light adaptation. The other end of the spectrum is dark adaptation which is the adjustment from an illuminated area to darkness.

Divided attention

Divided attention occurs when mental focus is on multiple tasks or ideas at once. Also known as multitasking, individuals do this all the time. Examples are singing along to a song while driving, having a conversation while walking, or listening to music while grocery shopping. Divided attention does decrease the amount of attention being placed on any one task or idea if there are multiple focuses going on at once. For example, if you answer a friend's question while you are reading a book your concentration on the book wanes as you focus on responding to your friend.

Electroencephalogram (EEG)

EEG Electroencephalography (EEG) is the measurement of the electrical activity of the brain by recording from electrodes placed on the scalp. The resulting traces are known as an electroencephalogram (EEG) and represent an electrical signal from a large number of neurons. EEGs are frequently used in experimentation because the process is non-invasive to the research subject. The EEG is capable of detecting changes in electrical activity in the brain on a millisecond-level. It is one of the few techniques available that has such high temporal resolution.

Freud

Freud (1856-1939) is known as the Father of Psychoanalysis, a method for treating psychological pathology by means of dialogue between the patient and the psychoanalyst. During psychoanalysis, the patient talks about whatever thoughts come to mind, a process called "free association." The patient is also encouraged to talk about his wishes, fears, and dreams. The role of the analyst is to help the patient gain access to the unconscious conflicts that lie at the root of the psychological problem, and help him gain insight that will lead to resolution. One of Freud's most important contributions is the idea that the unconscious mind holds the key to understanding conscious thoughts and behavior, and the role that dreams play in unlocking what is hidden or repressed beneath conscious awareness.

Generalizability

Generalizability is another way of saying "ecological validity". Essentially this is the extent to which findings (from a study) can be generalized (or extended) to the those in natural settings (i.e., outside the lab). In virtually all studies there is a trade-off between experimental control and generalizability, but obviously you want to have both. The more control psychologists exert in a study the less they may be able to generalize. For example, when we take people out of their natural environment and study them in the lab, we are exerting some control over them and, as a result, possibly limiting how much we can generalize the findings to all people in natural settings.

Gestalt laws of organization

Gestalt is a psychology term which means "unified whole". It refers to theories of visual perception developed by German psychologists in the 1920s. These theories attempt to describe how people tend to organize visual elements into groups or unified wholes when certain principles are applied. These principles are: Similarity Similarity occurs when objects look similar to one another. People often perceive them as a group or pattern. Continuation Continuation occurs when the eye is compelled to move through one object and continue to another object. Closure Closure occurs when an object is incomplete or a space is not completely enclosed. If enough of the shape is indicated, people perceive the whole by filling in the missing information. Proximity Proximity occurs when elements are placed close together. They tend to be perceived as a group. Figure and Ground The eye differentiates an object form its surrounding area. a form, silhouette, or shape is naturally perceived as figure (object), while the surrounding area is perceived as ground (background). Balancing figure and ground can make the perceived image more clear. Using unusual figure/ground relationships can add interest and subtlety to an image. http://graphicdesign.spokanefalls.edu/tutorials/process/gestaltprinciples/gestaltprinc.htm

Signal-Detection theory

Have you ever done that thing where you could swear you hear your phone ringing or feel it vibrating in your pocket, but then you go to check it and nobody was calling? Of course you have. We all have. It's a common occurrence, and there's actually a scientific reason for it. No, it's not that you're going crazy, and yes, I am aware that this is the first explanation that goes through everyone's mind. For a long time, psychologists have been interested in how our minds become aware of stimuli, of factors in the environment around us that can be detected through the five senses of sight, hearing, taste, touch, and smell. How do we notice these stimuli? Why do we sometimes not notice them, and why do we detect them when they're not really there? The leading explanation: signal detection theory, which at its most basic, states that the detection of a stimulus depends on both the intensity of the stimulus and physical/psychological state of the individual. Basically, we notice things based on how strong they are and on how much we're paying attention.

Survey research

In research of human subjects, a survey is a list of questions aimed at extracting specific data from a particular group of people. Surveys may be conducted by phone, mail, via the internet, and sometimes face-to-face on busy street corners or in malls. A survey is a data collection tool used to gather information about individuals. Surveys are commonly used in psychology research to collect self-report data from study participants. A survey may focus on factual information about individuals, or it might aim to obtain the opinions of the survey takers.

Dendrite

Information comes into the neuron through the Dendrites from other neurons. Dendrites (from Greek δένδρον déndron, "tree") are the branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project.

Correlation coefficients

Instead of drawing a scattergram a correlation can be expressed numerically as a coefficient, ranging from -1 to +1. When working with continuous variables, the correlation coefficient to use is Pearson's r. The correlation coefficient (r) indicates the extent to which the pairs of numbers for these two variables lie on a straight line. Values over zero indicate a positive correlation, while values under zero indicate a negative correlation. Strengths of Correlations 1. Correlation allows the researcher to investigate naturally occurring variables that maybe unethical or impractical to test experimentally. For example, it would be unethical to conduct an experiment on whether smoking causes lung cancer. 2. Correlation allows the researcher to clearly and easily see if there is a relationship between variables. This can then be displayed in a graphical form. Limitations of Correlations 1. Correlation is not and cannot be taken to imply causation. Even if there is a very strong association between two variables we cannot assume that one causes the other. For example suppose we found a positive correlation between watching violence on T.V. and violent behavior in adolescence. It could be that the cause of both these is a third (extraneous) variable - say for example, growing up in a violent home - and that both the watching of T.V. and the violent behavior are the outcome of this. 2. Correlation does not allow us to go beyond the data that is given. For example suppose it was found that there was an association between time spent on homework (1/2 hour to 3 hours) and number of G.C.S.E. passes (1 to 6). It would not be legitimate to infer from this that spending 6 hours on homework would be likely to generate 12 G.C.S.E. passes. https://www.simplypsychology.org/correlation.html

Why do we sleep?

Most theorists agree that sleep has value as a recuperative and adaptive function in the lives of humans. The relatively high metabolic needs of mammals and birds to maintain a constant body temperature in a wide range of environmental temperatures suggests that the periodic decreases in metabolic rate and body temperature that occur in NREM sleep allow for recuperation and restitution of body tissues. For example, even though the function of stage 2 NREM sleep is not clear, approximately half of human sleep time is spent in this stage. It is also theorized that REM sleep provides a period of recuperation of mental activities and preparation for wakefulness. During REM sleep it is believed that there is increased metabolic activity in the brain so that during waking hours it is more receptive to new information and can assimilate it more easily.

Neuron

Neuron is a specialized nerve cell that receives, processes, and transmits information to other cells in the body. We have a fixed number of neurons, which means they do not regenerate. About 10,000 neurons die everyday, but since we start out with between ten and 100 billion (Hooper & Teresi, 1987), we only lose about 2% over our lifetime.

Neuroplasticity

Neuroplasticity, also called brain plasticity, is the process in which your brain's neural synapses and pathways are altered as an effect of environmental, behavioral, and neural changes. When it comes to neuroplasticity, the brain is a lot like film. When you photograph a picture, of say, a mountain, you're exposing the film to new information. It reacts to the light, and its makeup changes in order to record the image of that mountain. In the same way, your brain's makeup changes when it's exposed to new information, so that it may retain that information. Neuroplasticity happens continually as you learn and memorize new data, and as your brain develops; however, it can also be spurred by a physical trauma. In such cases, neuroplasticity serves as an adaptive mechanism that allows someone to compensate for function loss after suffering a bodily injury. For example, if someone suffers a brain injury, neuroplasticity allows the brain to 'rewire' itself in order to restore or maximize brain functioning by rebuilding neural circuits and allowing an uninjured part of the brain to take over the damaged part.

Absolute threshold

Often used in neuroscience and experimental research. An absolute threshold is the smallest detectable level of a stimulus. For example, in an experiment on sound detention, researchers may present a sound with varying levels of volume. The smallest level that a participant is able to hear is the absolute threshold. However, it is important to note that at such low levels, participants may only detect the stimulus part of the time. Because of this, the absolute threshold is usually defined as the smallest level of a stimulus that a person is able to detect 50 percent of the time.

Perception

Perception can be defined as our recognition and interpretation of sensory information. Perception also includes how we respond to the information. We can think of perception as a process where we take in sensory information from our environment and use that information in order to interact with our environment. Perception allows us to take the sensory information in and make it into something meaningful. For example, let's look at our perception of words. Each letter of the alphabet is in itself a singular letter. When we perceive words, we think of them as one singular unit that is made up of smaller parts called letters. It is through this organization of letters into words that we are able to make something meaningful. That is, we perceive an entire word, and this word has a specific meaning that can be found in the dictionary. Perception is also necessary for us to survive in our environment. For example, before parents feed their babies microwaved food, they taste it in order to make sure that the temperature isn't too hot. This involves using sensory information (touch and taste) to make sure that the food is not dangerous for the infant. Before we cross a busy street, we rely on our hearing and sight to make sure a car is not coming. Without the sensory information, we would not be able to judge which food was too hot or when an appropriate time to cross the street would be, which could put us and our children in danger.

Physiological

Physiological psychology is a subdivision of behavioral neuroscience (biological psychology) that studies the neural mechanisms of perception and behavior through direct manipulation of the brains of nonhuman animal subjects in controlled experiments.

Place theory of hearing

Place theory is a theory of hearing which states that our perception of sound depends on where each component frequency produces vibrations along the basilar membrane. The place theory of hearing is used to explain how we distinguish high-pitched sounds that possess a frequency that exceeds 5,000 hertz. According to the place theory of hearing, we can hear different pitches due to specific sound frequencies causing vibrations in specific parts on the basilar membrane of the cochlea. In other words, different parts of the cochlea are activated by different frequencies. Each location on the basilar membrane possesses a particular characteristic frequency. For example, a sound that measures 6,000 hertz would stimulate the spot along the basilar membrane that possesses a characteristic frequency of 6,000 hertz. The brain detects the pitch based on the position of the hair cells that transmitted the neural signal.

REM sleep

REM Sleep During REM sleep: -The brain becomes more active -Body becomes relaxed and immobilized -Dreams occur -Eyes move rapidly Most dreaming occurs during the fourth stage of sleep, known as rapid eye movement (REM) sleep. REM sleep is characterized by eye movement, increased respiration rate, and increased brain activity. The American Sleep Foundation suggests that people spend approximately 20 percent of their total sleep in this stage. REM sleep is also referred to as paradoxical sleep because while the brain and other body systems become more active, muscles become more relaxed. Dreaming occurs due to increased brain activity, but voluntary muscles become immobilized.

Sensation

Sensation is the process that allows our brains to take in information via our five senses, which can then be experienced and interpreted by the brain. Sensation occurs thanks to our five sensory systems: vision, hearing, taste, smell and touch. Each of these systems maintains unique neural pathways with the brain, which allows them to transfer information from the environment to the brain very rapidly. Without sensation we would not be able to enjoy the sunny spring day at the park. Each sensory system contains unique sensory receptors, which are designed to detect specific environmental stimuli. Once detected, sensory receptors convert environmental stimulus energy into electrochemical neural impulses. The brain then interprets those neural messages, which allow the brain to experience and make decisions about the environment. Let's take a little bit closer look at the process of sensation by examining each of the five sensory systems involved.

Spreading activation

Spreading activation is a model of working memory, also known as short-term memory, that seeks to explain how the mind processes related ideas, especially semantic or verbal concepts. The spreading activation model is one way cognitive psychologists explain the priming effect, which is the observable phenomenon that a person is able to more quickly recall information about a subject once a related concept has been introduced. According to this model, semantic long-term memory consists of a vast, interrelated network of concepts. When a person is presented with any concept, the concepts most closely connected to it are activated in that person's mind, preparing or "priming" him or her to recall information related to any of them. According to the theory of spreading activation, each semantic concept has a node in the neural network that is activated at the same time as the nodes for related concepts. If a person is presented with the concept "dog," nodes for concepts like "bark," "beagle" and "pet" might be activated, priming him or her to think about these related words. Depending on which concept relating to "dog" is presented next, the person is able to recall any information that might be relevant to the task at hand. One such task might be to evaluate the accuracy of semantic statements. The person could, for instance, more quickly verify the statement "A beagle is a dog" if he or she already knows that the topic at hand is "dog."

Structuralism

Structuralism was the name given to the approach pioneered by Wilhelm Wundt. The term originated from Edward Titchener, an American psychologist who had been trained by Wundt. Structuralism relied on trained introspection, a research method whereby subjects related what was going on in their minds while performing a certain task. However, it proved to be unreliable method because there was too much individual variation in the experiences and reports of research subjects.

Zajonc (1968) experiment on mere exposure

Summary Zajonc conducted four experiments, each of which provided overwhelming to strong support for the hypothesis that mere repeated exposure of an individual to a stimulus object enhances his or her attitude toward it. For example, in experiment #3, subjects were shown nonsense symbols that resembled Chinese characters. Each character was shown from 0-25 times. The subjects were then asked to rate how they felt about each character. Results Eleven out of twelve times, the character was liked better when it was in the high frequency category. Applied Ideas The mere exposure effect is an example of how irrational we can be. In no way does mere exposure mean that something is more trustworthy or deserving of positive feelings. This idea explains attachments to both animate and inanimate objects, and why sometimes it is hard to throw things away. Fear not; this same irrational bias that has caused you to form attachments to things you no longer have also works to irrationally help you form new attachments!

Information processing

The Information Processing Model is a framework used by cognitive psychologists to explain and describe mental processes. The model likens the thinking process to how a computer works. Just like a computer, the human mind takes in information, organizes and stores it to be retrieved at a later time. Just as the computer has an input device, a processing unit, a storage unit, and an output device, so does the human mind have equivalent structures.

Feature detectors

The ability to detect certain types of stimuli, like movements, shape, and angles, requires specialized cells in the brain called feature detectors. Without these, it would be difficult, if not impossible, to detect a round object, like a baseball, hurdling toward you at 90 miles per hour.

Know the Central & Peripheral Nervous Systems and their components

The central nervous system (CNS) is comprised of the brain and spinal cord. The CNS receives sensory information from the nervous system and controls the body's responses. The CNS is differentiated from the peripheral nervous system, which involves all of the nerves outside of the brain and spinal cord that carry messages to the CNS. The central nervous system is named as such because it plays the primary role in receiving information from various areas of the body and then coordinating this activity to produce the body's responses. --The Structure of the Central Nervous System The brain controls many of the body's functions including sensation, thought, movement, awareness, and memory. The spinal cord connects to the brain via the brain stem and then runs down through the spinal canal located inside the vertebra. The spinal cord carries information from various parts of the body to and from the brain. In the case of some reflex movements, responses are controlled by spinal pathways without involvement from the brain. Neurons are the building blocks of the central nervous system. Billions of these nerve cells can be found throughout the body and communicate with one another to produces physical responses and actions. An estimated 86 billion neurons can be found in the brain alone! Since the CNS is so important, it is protected by a number of structures. First, the entire CNS is enclosed in bone. The brain is protected by the skull while the spinal cord is protected by the vertebra of the spinal column. The brain and spinal cord are both covered with protective tissue known as meninges. The entire CNS is also immersed in a substance known as cerebrospinal fluid, which forms a chemical environment to allow nerve fibers to transmit information effectively as well as offering yet another layer of protection from potential damage. The surface of the brain is known as the cerebral cortex. The surface of the cortex appears bumpy thanks to the grooves and folds of the tissue. Each groove is known as a sulcus while each bump is known as a gyrus. The largest part of the brain is known as the cerebrum and is responsible for things such as memory, speech, voluntary behaviors, and thought. The cerebrum is divided into two hemispheres, a right hemisphere and a left hemisphere. The brain's right hemisphere controls movements on the body's left side, while the left hemisphere controls movements on the body's right side. While some functions do tend to be lateralized, this does not suggest that they are "left brained" or "right brained" thinkers, as the old myth implies. Some brain functions tend to be lateralized, but both sides of the brain work together to produce various functions. Each hemisphere of the brain is then divided into four interconnected lobes: The frontal lobes are associated with higher cognition, voluntary movements, and language. The parietal lobes are associated with processing sensory information. The temporal lobes are associated with hearing and interpreting sounds as well as the formation of memories. The occipital lobes are associated with visual processes. ---Peripheral nervous system The nerves in the peripheral nervous system (PNS) connect the central nervous system (CNS) to sensory organs (such as the eye and ear), other organs of the body, muscles, blood vessels and glands. The peripheral nerves include the 12 cranial nerves, the spinal nerves and roots, and what are called the autonomic nerves. The autonomic nerves are concerned with automatic functions of the body. Specifically, autonomic nerves are involved with the regulation of the heart muscle, the tiny muscles lining the walls of blood vessels, and glands. The nerves that make up the peripheral nervous system are actually the axons or bundles of axons from neuron cells. In some cases, these nerves are very small but some nerve bundles are so large that they can be easily seen by the human eye. The peripheral nervous system itself is divided into two parts: The somatic nervous system The autonomic nervous system Each of these components plays a critical role in how the peripheral nervous system operates. The Somatic Nervous System The somatic system is the part of the peripheral nervous system responsible for carrying sensory and motor information to and from the central nervous system. The somatic nervous system derives its name from the Greek word soma, which means "body." The somatic system is responsible for transmitting sensory information as well as for voluntary movement. This system contains two major types of neurons: Sensory neurons (or afferent neurons) that carry information from the nerves to the central nervous system. It is these sensory neurons that allow us to take in sensory information and send it to the brain and spinal cord. Motor neurons (or efferent neurons) that carry information from the brain and spinal cord to muscle fibers throughout the body. These motor neurons allow us to take physical action in response to stimuli in the environment. The Autonomic Nervous System The autonomic system is the part of the peripheral nervous system responsible for regulating involuntary body functions, such as blood flow, heartbeat, digestion, and breathing. In other words, it is the autonomic system that control aspects of the body that are usually not under voluntary control. This system allows these functions to take place without needing to consciously think about them happening. This system is further divided into two branches: The sympathetic system regulates the flight-or-fight responses. This system prepares the body to expend energy and deal with potential threats in the environment. When action is needed, the sympathetic system will trigger a response by speeding up the heart rate, increasing breathing rate, increasing blood flow to muscles, activating sweat secretion, and dilating the pupils. This allows the body to respond quickly in situations that require immediate action. In some cases, we might stay and fight the threat, while in other cases we may instead flee from the danger. The parasympathetic system helps maintain normal body functions and conserve physical resources. Once a threat has passed, this system will slow the heart rate, slow breathing, reduce blood flow, to muscles and constrict the pupils. This allows us to return our bodies to a normal resting state.

Cerebral Cortex

The cerebral cortex is the most important part of our brain (at least in the field of psychology) because it is what makes us human. The cerebral cortex (sometimes referred to as called "gray matter", is actually densely packed neurons. We actually are born with more neurons in our cerebral cortex than we have now, but they are young and inexperienced. As you get older the neurons learn to work together forming what we call neural networks.

Cocktail Party Effect

The cocktail party effect is the phenomenon of being able to focus one's auditory attention on a particular stimulus while filtering out a range of other stimuli, as when a partygoer can focus on a single conversation in a noisy room. Your brain helps you selectively focus on the person you are talking too and 'mutes' the other conversation, music, and general noise around you.

Difference thresholds

The difference threshold, also known as the just noticeable difference (jnd), is the minimum difference in stimulation that a person can detect 50 percent of the time. We experience the difference threshold as a just noticeable difference. For example, let's say I asked you to put your hand out and in it I placed a pile of sand. Then, I add tiny amounts of sand to your hand and ask you to tell me when you notice any change in the overall weight. As soon as you can detect any change in the weight, that difference between the weight of the sand before I added that last bit of sand and the amount of sand after I added it, is the difference threshold.

Independent Variable

The experimental factor that is manipulated; the variable whose effect is being studied.

Frequency theory of hearing

The frequency theory of hearing states that the frequency of the auditory nerve's impulses corresponds to the frequency of a tone, which allows us to detect its pitch. The way it works is that sound waves cause the entire basilar membrane to vibrate at different rates, which, in turn, causes the neural impulses to be transmitted at different rates. Basically, when we hear a musical note, it causes specific vibrations in our ears that lets us hear that specific pitch. Lower notes vibrate at slower speeds, while higher notes vibrate at higher speeds. As pitch increases, nerve impulses of the same frequency are sent to the auditory nerve. This means that a tone with a frequency of 700 hertz produces 700 nerve impulses per second. It is the speed in which the neural signals move along the brain that determine the pitch.

Hippocampus

The hippocampus is a part of the limbic system. The limbic system is the area in the brain that is associated with memory, emotions, and motivation. The limbic system is located just above the brain stem and below the cortex. The hippocampus itself is highly involved with our memories. The limbic system plays a huge part in our survival roles. It is responsible for our fight or flight responses. This is when a person feels like he is in danger and either needs to fight his way out or run away from the situation. The limbic system also gives us that 'gut feeling.' The limbic system, including the hippocampus, is located in a very protected area of the brain. The hippocampus is a horseshoe-shaped structure. There are actually two pieces that are mirrored in pairs. One of the pairs is located in the right hemisphere. Its mirrored other half of the horseshoe is located in the left hemisphere.

Myelin sheath

The insulating envelope of myelin that surrounds the core of a nerve fiber or axon and that facilitates the transmission of nerve impulses, formed from the cell membrane of the Schwann cell in the peripheral nervous system and from oligodendroglia cells. Also called medullary sheath. Myelin is a fatty substance that covers neurons. Around your neurons is a myelin sheath (a layer of myelin) that helps increase the speed at which information can travel on the neurons. If you could look at a neuron you would see the sheath covering the axon of the neuron in a way that looks like a row of sausage links.

Limbic system

The limbic system combines higher mental functions and primitive emotion into one system. The limbic system, located just beneath the cerebrum on both sides of the thalamus, is not only responsible for our emotional lives but also many higher mental functions, such as learning and formation of memories. The primary structures within the limbic system include the amygdala, hippocampus, thalamus, hypothalamus, basal ganglia, and cingulate gyrus. The amygdala is the emotion center of the brain, while the hippocampus plays an essential role in the formation of new memories about past experiences. The thalamus and hypothalamus are associated with changes in emotional reactivity. The cingulate gyrus coordinates smells and sights with pleasant memories, induces an emotional reaction to pain, and helps regulate aggressive behavior. The basal ganglia is a group of nuclei lying deep in the subcortical white matter of the frontal lobes; its functions include organizing motor behavior and coordinating rule-based, habit learning.

Mere exposure

The mere-exposure effect is a psychological phenomenon by which people tend to develop a preference for things merely because they are familiar with them. In social psychology, this effect is sometimes called the familiarity principle. Have you ever met someone you didn't like very much at first and then over time, even if you didn't really have personal interactions with the person you started liking them (or disliking them less)? This might have been due to the mere exposure effect in which you begin to like something simply because you are exposed to it over and over again. I bet if you think about it you can come up with all sorts of things that you like simply because you are exposed to it repeatedly. There are many advertisers who bombard you with their products for this reason.

Occipital, Parietal, & Frontal lobes

The occipital lobe--is located at the back portion of the brain and is associated with interpreting visual stimuli and information. The primary visual cortex, which receives and interprets information from the retinas of the eyes, is located in the occipital lobe. Damage to this lobe can cause visual problems such as difficulty recognizing objects, an inability to identify colors, and trouble recognizing words. The parietal lobe--is located in the middle section of the brain and is associated with processing tactile sensory information such as pressure, touch, and pain. A portion of the brain known as the somatosensory cortex is located in this lobe and is essential to the processing of the body's senses. The frontal lobe--is located at the front of the brain and is associated with reasoning, motor skills, higher level cognition, and expressive language. At the back of the frontal lobe, near the central sulcus, lies the motor cortex. This area of the brain receives information from various lobes of the brain and utilizes this information to carry out body movements. Damage to the frontal lobe can lead to changes in sexual habits, socialization, and attention as well as increased risk-taking.

Opponent-Process Theory of color vision

The opponent process theory of color vision suggests that our ability to perceive color is controlled by three receptor complexes with opposing actions. These three receptors complexes are the red-green complex, the blue-yellow complex, and the black-white complex. According to the opponent process theory, these cells can only detect the presence of one color at a time because the two colors oppose one another. You do not see greenish-red because the opponent cells can only detect one of these colors at a time.

Reuptake

The reabsorption of a secreted substance by the cell that originally produced and secreted it. The process of reuptake, for example, affects serotonin. Serotonin is a neurotransmitter (a chemical messenger). It is produced by nerve cells in the brain and is used by nerves to communicate with one another. A nerve releases the serotonin that it has produced into the space surrounding it. The serotonin either travels across that space and attaches to receptors on the surface of nearby nerves or it attaches to receptors on the surface of the nerve that produced it, to be taken up by the nerve, recycled, and released again. This process is referred to as reuptake. A balance is reached for serotonin between attachment to the nearby nerves and reuptake. A medication that acts as a selective serotonin reuptake inhibitor (SSRI) blocks the reuptake of serotonin and thereby changes the level of serotonin in the brain.

Stages of sleep

The sleep cycle: A sleep cycle lasts about 90 minutes and during that time we move through five stages of sleep. The first four stages make up our non-rapid eye movement (NREM) sleep, and the fifth stage is when rapid eye movement (REM) sleep occurs. NREM Stage 1 Stage 1 is the beginning of the sleep cycle and is a relatively light stage of sleep. Stage 1 can be considered a transition period between wakefulness and sleep. In Stage 1, the brain produces high amplitude theta waves, which are very slow brain waves. This period of sleep lasts only a brief time (around five to 10 minutes). If you awaken someone during this stage, they might report that they were not really asleep. NREM Stage 2 During stage 2 sleep: -People become less aware of their surroundings -Body temperature drops -Breathing and heart rate become more regular Stage 2 is the second stage of sleep and lasts for approximately 20 minutes. The brain begins to produce bursts of rapid, rhythmic brain wave activity known as sleep spindles. Body temperature starts to decrease and heart rate begins to slow. According to the American Sleep Foundation, people spend approximately 50 percent of their total sleep in this stage. NREM Stage 3 (and 4) During stage 3 sleep: -Muscles relax -Blood pressure and breathing rate drop -Deepest sleep occurs -This stage was previously divided into stages 3 and 4. Deep, slow brain waves known as delta waves begin to emerge during stage 3 sleep. This stage is also sometimes referred to as delta sleep. During this stage, people become less responsive and noises and activity in the environment may fail to generate a response. It also acts as a transitional period between light sleep and a very deep sleep. Older studies suggested that bed-wetting was most likely to occur during this deep stage of sleep, but some more recent evidence suggests that such bed-wetting can also occur at other stages. Sleepwalking also tends to occur most often during the deep sleep of this stage.

Autonomic and Somatic systems

The somatic system is the part of the peripheral nervous system responsible for carrying sensory and motor information to and from the central nervous system. The somatic nervous system derives its name from the Greek word soma, which means "body." The somatic system is responsible for transmitting sensory information as well as for voluntary movement. This system contains two major types of neurons: Sensory neurons (or afferent neurons) that carry information from the nerves to the central nervous system. It is these sensory neurons that allow us to take in sensory information and send it to the brain and spinal cord. Motor neurons (or efferent neurons) that carry information from the brain and spinal cord to muscle fibers throughout the body. These motor neurons allow us to take physical action in response to stimuli in the environment. The Autonomic Nervous System The autonomic system is the part of the peripheral nervous system responsible for regulating involuntary body functions, such as blood flow, heartbeat, digestion, and breathing. In other words, it is the autonomic system that control aspects of the body that are usually not under voluntary control. This system allows these functions to take place without needing to consciously think about them happening. This system is further divided into two branches: The sympathetic system regulates the flight-or-fight responses. This system prepares the body to expend energy and deal with potential threats in the environment. When action is needed, the sympathetic system will trigger a response by speeding up the heart rate, increasing breathing rate, increasing blood flow to muscles, activating sweat secretion, and dilating the pupils. This allows the body to respond quickly in situations that require immediate action. In some cases, we might stay and fight the threat, while in other cases we may instead flee from the danger. The parasympathetic system helps maintain normal body functions and conserve physical resources. Once a threat has passed, this system will slow the heart rate, slow breathing, reduce blood flow, to muscles and constrict the pupils. This allows us to return our bodies to a normal resting state.

Sympathetic and Parasympathetic systems

The sympathetic system regulates the flight-or-fight responses. This system prepares the body to expend energy and deal with potential threats in the environment. When action is needed, the sympathetic system will trigger a response by speeding up the heart rate, increasing breathing rate, increasing blood flow to muscles, activating sweat secretion, and dilating the pupils. This allows the body to respond quickly in situations that require immediate action. In some cases, we might stay and fight the threat, while in other cases we may instead flee from the danger. The parasympathetic system helps maintain normal body functions and conserve physical resources. Once a threat has passed, this system will slow the heart rate, slow breathing, reduce blood flow, to muscles and constrict the pupils. This allows us to return our bodies to a normal resting state.

Reliability

The term reliability in psychological research refers to the consistency of a research study or measuring test. For example, if a person weighs themselves during the course of a day they would expect to see a similar reading. Scales which measured weight differently each time would be of little use.

Thalamus

The thalamus is a structure deep within the brain stem that receives sensory information from the nervous system and passes the information to the cerebral cortex and other parts of the brain.It acts as a director of information related to bodily functions such as seeing, sleeping, hearing, waking, tasting, and touching.

Trichromatic theory of color vision

The trichromatic theory of color vision is based on the premise that there are three classes of cone receptors subserving color vision. This theory has a very long history dating back to the 18th century. One of the more important empirical aspects of this theory is that it is possible to match all of the colors in the visible spectrum by appropriate mixing of three primary colors. Which primary colors are used is not critically important as long as mixing two of them does not produce the third. Modern color scientists have put great effort into determining that there are indeed three classes of cones, that their outer segments contain spectrally selective photopigments and in determining the spectral absorbance of these photopigments. During the last 15 or so years geneticists have and continue to investigate the genetic basis underlying trichromatic vision. They have indeed been able to identify the genes that are responsible for the receptor photopigments. It was popular in the first half of the 20th century for authors to pit the trichromatic theory against the opponent processes theory. But in fact both theories help to explain how our color vision system works. The trichromatic theory operates at the receptor level and the opponent processes theory applies to the subsequent neural level of color vision processing.

Top-down vs. Bottom-up processing

There are two general processes involved in sensation and perception. Bottom-up processing refers to processing sensory information as it is coming in. In other words, if I flash a random picture on the screen, your eyes detect the features, your brain pieces it together, and you perceive a picture of an eagle. What you see is based only on the sensory information coming in. Bottom-up refers to the way it is built up from the smallest pieces of sensory information. Top-down processing, on the other hand, refers to perception that is driven by cognition. Your brain applies what it knows and what it expects to perceive and fills in the blanks, so to speak.

Corpus Callosum

This area contains the largest bundle of nerve fibers in the brain and connects the two sides (hemispheres) of the brain. The corpus callosum doesn't just sit there, it is responsible for allowing the two hemispheres to communicate with each other and share information. Thus, the corpus callosum carries massages between the left and right hemispheres of the brain.

Transduction

Transduction in general is the transportation or transformation of something from one form, place, or concept to another. ... Furthermore, transduction is defined as what takes place when many sensors in the body convert physical signals from the environment into encoded neural signals sent to the central nervous system. Technically speaking, transduction is the process of converting one form of energy into another. As it relates to psychology, transduction refers to changing physical energy into electrical signals (neural impusles) that can make their way to the brain. For example, your ears receive energy (sound waves) and transduce (or convert) this energy into neural messages that make their way to your brain and are processed as sounds.

Wilhelm Wundt

Wilhelm Wundt opened the Institute for Experimental Psychology at the University of Leipzig in Germany in 1879. This was the first laboratory dedicated to psychology, and its opening is usually thought of as the beginning of modern psychology. Indeed, Wundt is often regarded as the father of psychology Wundt was important because he separated psychology from philosophy by analyzing the workings of the mind in a more structured way, with the emphasis being on objective measurement and control.

Reticular formation

a diffuse network of nerve pathways in the brainstem connecting the spinal cord, cerebrum, and cerebellum, and mediating the overall level of consciousness. The reticular formation is a region in the pons involved in regulating the sleep-wake cycle and filtering incoming stimuli to discriminate irrelevant background stimuli. The reticular formation consists of more than 100 small neural networks with varied functions including motor control, cardiovascular control, pain modulation, sleep, and habituation. Bilateral damage to the reticular formation of the midbrain may lead to coma or death. Traditionally, the nuclei of the reticular formation are divided into three columns: the median column or the Raphe nuclei, the medial column or the magnocellular nuclei, and the lateral column or parvocellular nuclei.

Case study

a process or record of research in which detailed consideration is given to the development of a particular person, group, or situation over a period of time. Case study in psychology refers to the use of a descriptive research approach to obtain an in-depth analysis of a person, group, or phenomenon. A variety of techniques may be employed including personal interviews, direct-observation, psychometric tests, and archival records.

Amygdala

a roughly almond-shaped mass of gray matter inside each cerebral hemisphere, involved with the experiencing of emotions. Amygdala is the integrative center for emotions, emotional behavior, and motivation

Sample

a subset of the population a small part of anything or one of a number, intended to show the quality, style, or nature of the whole; specimen.

William James

an American philosopher and psychologist who was also trained as a physician. The first educator to offer a psychology course in the United States,[3] James was one of the leading thinkers of the late nineteenth century and is believed by many to be one of the most influential philosophers the United States has ever produced, while others have labeled him the "Father of American psychology".

Random Assignment

assigning participants to experimental and control groups by random chance Random assignment or random placement is an experimental technique for assigning human participants or animal subjects to different groups in an experiment (e.g., a treatment group versus a control group) using randomization, such as by a chance procedure (e.g., flipping a coin) or a random number generator. This ensures that each participant or subject has an equal chance of being placed in any group.

Lateralization

brain function is the tendency for some neural functions or cognitive processes to be more dominant in one hemisphere than the other. The medial longitudinal fissure separates the human brain into two distinct cerebral hemispheres, connected by the corpus callosum.

4 types of brain-imaging techniques (fMRI, PET, CAT, TMS)

fMRI Functional magnetic resonance imaging, or fMRI, is a technique for measuring brain activity. It works by detecting the changes in blood oxygenation and flow that occur in response to neural activity - when a brain area is more active it consumes more oxygen and to meet this increased demand blood flow increases to the active area. fMRI can be used to produce activation maps showing which parts of the brain are involved in a particular mental process. PET Positron Emission Tomography (PET) uses trace amounts of short-lived radioactive material to map functional processes in the brain. When the material undergoes radioactive decay a positron is emitted, which can be picked up be the detector. Areas of high radioactivity are associated with brain activity. CT (AKA CAT) Computed tomography (CT) scanning builds up a picture of the brain based on the differential absorption of X-rays. During a CT scan the subject lies on a table that slides in and out of a hollow, cylindrical apparatus. An x-ray source rides on a ring around the inside of the tube, with its beam aimed at the subjects head. After passing through the head, the beam is sampled by one of the many detectors that line the machine's circumference. Images made using x-rays depend on the absorption of the beam by the tissue it passes through. Bone and hard tissue absorb x-rays well, air and water absorb very little and soft tissue is somewhere in between. Thus, CT scans reveal the gross features of the brain but do not resolve its structure well. TMS a noninvasive procedure that uses magnetic fields to stimulate nerve cells in the brain to improve symptoms of depression. TMS is typically used when other depression treatments haven't been effective. During a TMS session, an electromagnetic coil is placed against your scalp near your forehead. The electromagnet painlessly delivers a magnetic pulse that stimulates nerve cells in the region of your brain involved in mood control and depression. And it may activate regions of the brain that have decreased activity in people with depression. Though the biology of why rTMS works isn't completely understood, the stimulation appears to affect how this part of the brain is working, which in turn seems to ease depression symptoms and improve mood. Treatment for depression involves delivering repetitive magnetic pulses, so it's called repetitive TMS or rTMS.

Random Sample

in this type of sample, every individual has a known and equal chance of being selected A random sample is a sample in which each member of the population has an equal chance of being selected to represent the whole.

Synapse

n the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron. A synapse is a small gap at the end of a neuron that allows a signal to pass from one neuron to the next. Synapses are found where nerve cells connect with other nerve cells. The term synapse was first introduced in 1897 by physiologist Michael Foster in his Textbook of Physiology and is derived from the Greek synapsis, meaning "conjunction." What Do Synapses Do? When a nerve signal reaches the end of the neuron, it cannot simply continue to the next cell. Instead, it must trigger the release of neurotransmitters which can then carry the impulse across the synapse to the next neuron. Once a nerve impulse has triggered the release of neurotransmitters, these chemical messengers cross the tiny synaptic gap and taken up by specialized receptors on the surface of the next cell. These receptors act much like a lock and the neurotransmitters function much like a key. This process then converts the chemical signal back into an electrical signal. If the signal is strong enough, it will be propagated down the next neuron by an action potential until it once again reaches a synapse and the process is repeated once more.

Perception below the level of awareness (subliminal perception)

perception of or reaction to a stimulus that occurs without awareness or consciousness Subliminal perception is supposed to occur when a stimulus is too weak to be perceived yet a person is influenced by it.

Action potential

the change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell. The action potential threshold in a neuron is the point of depolarization at which the neuron fires, transmitting information to another neuron. Psychologists use the concept of action potential threshold to explain how neurons send information to each other. A neuron transmits information via electric impulses sent through its axon. When a neuron is inactive, more positively charged ions lie outside the axon membrane than within it. Upon stimulation, the axon membrane admits more sodium ions, rendering the neuron more positively charged. When the neuron reaches a certain point of depolarization known as the action potential threshold, it will fire; if it does not reach that point, it will not fire. The action potential of a neuron is always the same.

Naturalistic Observation

watching behavior in real-world settings without trying to manipulate the situation Naturalistic observation is a research method commonly used by psychologists and other social scientists. This technique involves observing subjects in their natural environment. This type of research is often utilized in situations where conducting lab research is unrealistic, cost prohibitive or would unduly affect the subject's behavior.