Unit 4: Sensation & Perception AP Practice & Unit Review
The structure of the ear that is responsible for gathering sound initially is the (A) pinna (B) tympanic membrane (C) cochlea (D) semicircular canals (E) stapes
a
Our rods and cones electromagnetic energy into neural messages (A) adapt (B) accommodate (C) parallel process (D) transduce (E) perceptually set
d
Extrasensory Perception(ESP)
the controversial claim that perception can occur apart from sensory input; include telepathy, clairvoyane, and recognition
Hue
the dimension of color that is determined by the wavelenghth of light
Wavelength
the distance from one peak of one light or sound wave to the peak of the next
Selective Attention
the focusing of conscious awareness on a particular stimulus
Inner Ear
the innermost part of the ear, containg the cochlea, semicircular canals, and vestibular sacs
Retina
the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
Difference Threshold
the minimum difference between two stimuli required for detection 50 percent of the time. we experinece the difference threshold as a just noticeable difference
Absolute Threshold
the minimum stimulation needed to detect a particular stimulus 50 percent of the time
Frequency
the number of complete wavelengths that pass a point in a given time
Figure-Ground
the organization of the visual field into objects(the figures) that stand out from their surroundings(the ground)
Grouping
the perceptual tendency to organize stimuli into coherent groups
Blind Spot
the point at which the optic nerve leaves th eye, creating a "blind" spot because no receptor cells are located there
Sensory Interaction
the principle that one sense may influence another, as when the smell o food influences its taste
Weber's Law
the principle that, to be percieved as different, two stimuli must differ by a constant percentage(rather than a constant amount)
Sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our enviroment
Accommodation
the process by which the ye's lens changes the shape to focus nera or far objects on the retina
Perception
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
Parallel Processing
the processing of many aspects of a problem simultaneously; the brain's natural mode of information processing for many fuctions, including vision
Vestibular Sense
the sense of body movement and position, including the sense of balance
Audition
the sense or act of hearing
Parapsychology
the study of paranormal phenomena, including ESP and pstchokinesis
Psychophysics
the study of relationships between the physical characterisitics of stimuli, such as their intensity, and our psychological experience of them
Opponenet-Process Theory
the theory that opposing retinal processes enable color vision. for example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
Young-Helmholtz Trichromatic(three-color) Theory
the theory that the retina contains three different color receptors-one most sensitive to red, one to green, one to blue- which, when stimulated in combination, can produce the perception of any color
Gate-Control Theory
the theroy that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain. the "gate" is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain
Lens
the transparent structire behind the pupil that changes shape to help focus images on the retina
Cochlear Implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
Phi Phenomenon
an illusion of movement created when two or more adjacent lights blink on and off in quick succession
Gestalt
an organized whole. his psychologists emphasized our tendency to integrate pieces of information into meaningful wholes
Bottom-Up Processing
analysis that begins with the sensory recpetors and works up to the brain's integration of sensory information
relative motion
as we move, objects that are actually stable may appear to move
light and shadow
nearby objects reflect more light to our eyes
Depth Perception
the ability to see objects in three-dimensions although the images that strike the retina are two-dimensionsal; allows us to judge distance
Primimg
the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response
Pupil
the adjustable opening in the center of the eye through which enters
Kinesthesis
the system for sensing the position and movement of individual body parts
Cones
retinal receptor cells that are concetarted near the center of the retina and that function in daylight or in well-lit conditions
Rods
retinal recpetors that detect blackl, white, and gray;necessary for peripheral and twiligt vision, when cones don't respond
How many smell receptors do we have?
0 BUT we have 1000 individual & in combo 10,000 discernible odors
What are the basic steps in forming sound waves into percieved sound?
1. OUTER EAR: collecting air pressure waves 2. MIDDLE EAR: mechanical waves 3. INNER EAR: fluid waves 4. AUDITORY NERVE: electrical waves 5. THE BRAIN: percieving sound
How many color receptors do we have?
3
19. How did the Gestalt psychologists understand perceptual organization?
A group of German scientists discovered (in the early 20th century) that when individuals are given a cluster of sensations, they organize them into whole or meaningful forms. This is known as a gestalt. We filter sensory information, and infer perception, in ways that make sense to us. Think of it this way: The whole is more than the sum of its parts. Ex. Figure 4.31 the Necker Cube
The point at which a person can detect a stimulus 50 percent of the time it is presented is called the ______. a) absolute threshold b) range threshold c) differential threshold d) noticeable threshold
A is the correct answer. Gustav Fechner investigated the sensitivity of the human sensory systems and called the lowest level of a stimulus that a person could detect half of the time the absolute threshold
Bottom up and top down processing
Bottom- up processing begins with the sensory receptors and works up to the brain's integration of sensory information. Top-down process is guided by higher-level-mental processes, like when we construct perceptions drawing on our experience and expectations
1. The most important role of sensory receptors is to _____________. a) coordinate communications within the body. b) regulate the body's response to pain. c) control skeletal muscle contractions. d) convert an external stimulus into an electrical-chemical message the nervous system can use.
D is the correct answer. Sensory receptors are the body's "antennae" to the outside world. Each sensory receptor type is specially designed to receive a specific external signal and convert it to an electrical-chemical signal.
What do we mean when we say that, in perception, " the whole is greater than the sum of its parts"?
Gestalt psychologists used this to describe our perceptual tendency to organize clusters of sensations into meaningful forms of coherent groups.
What is the energy we see as visible light?
Our eyes revive visible light energy and transduce (convert) it into neural messages our brain processes into what we consciously see. The light that enters our eyes is ELECTROMAGNETIC ENERGY that we perceive as color. The hue we see depends on the wavelength of light (red {longest}, orange, yellow, green, blue indigo, and violet {shortest}, and the brightness depends on the intensity.
23. How do perceptual constancies help us organize our sensations into meaningful perceptions?
Perceptual constancy is our ability to recognize objects without being deceived by changes in their shape, size, brightness, or color. *Shape constancy occurs when perceive that familiar objects (like an opening door) don't change in shape. When a door opens is shape goes from rectangular to more of trapezoid, yew we still perceive it as a rectangle. Figure 4.41 and Figure 4.40 *Size constancy occurs when we perceive objects as having a constant size, even as our distance varies. We know that a car viewed at a distance seem tiny, it can still carry people (because it isn't actually tiny). Figure 4.43 Seeing an object's distance gives us clues to its size, and knowing an object's actual size gives is clues about tis distance. *Lightness constancy occurs when we perceive an object as having a constant lightness even if its illumination changes. Figure 4.44 *Color constancy occurs when we perceive familiar objects as having consistent color, even if changing illumination alters the wavelengths reflect by the object. If you put on yellow tinted goggles, after a second you will perceive the snow as white again.
Psychophysics
Psychophysics is the study of the relationship between he physical characteristics of stimuli, like their intensity, and our psychological experience of them. We have energy all around us and pschophysicists study the energy we can detect and its effect on our psycholocical experience.
How do our expectations, contexts, and emotions influence our perceptions?
Seeing is believing, and believing in seeing. Expectations, assumptions, and experiences give us a perceptual set. A perceptual set is a mental predisposition to perceive one thing and not another. Once we form the wrong idea about reality it becomes very difficult to see the truth. Our perceptual sets are determined through experiences. Our experiences help us organize and interpret unfamiliar information. The surrounding context also helps us with our perceptions Emotions, motives, and culture also influence our perceptions. If a referee is told that a basketball team has been overly aggressive in past games, they will call more fouls. This affected their emotions If people are rewarded for perceiving ambiguous images in one way or another to view them to their benefit.
Sensation and perception
Sensation is the process by which our sensory receptors and nervous system revive and represent stimulus energies from our environment. Perception is the process of organizing and interpreting sensory information, enabling us to recognize meaningful object and events.
What is the rough distinction between sensation and perception?
Sensation: bottom-up process by which the physical sensory system receives and represents stimuli. Perception: top-down mental process of organizing and interpreting sensory input.
How do we experience smell?
Smell is a chemical sense (like taste). Smell occurs when molecules of a substance reach 5 million olfactory receptor cells at the top of each nasal cavity. These cells immediately signal the brain through neuron bypassing the thalamus, traveling to the brain's olfactory bulb, then to the temporal lobe, and to parts of the limbic system. There are 350 different receptor proteins embedded on the surface of nasal cavity neurons that recognize particular odor molecules. It is similar to a lock and key mechanism, the odor molecules slip into the receptor proteins and activate the neuron. There is not a distinct receptor for every scent, some odors are trigger through a combination of receptors. Our ability to identify odors peaks in early adulthood, and women are better able to detect scent than men. Scents can evoke memories (good and bade) because smell is primitive and the areas that process smell and memories (limbic system) are closely related.
What are the characteristics of air pressure waves that we hear as sound?
Sound waves are bands of air that are compressed or expanded. Our ears are able to detect the differences in air pressure and transform these changes into neural impulses that the brain is able to interpret into sound. Sound waves vary in length with changes the sounds frequency. Frequency determines the pitch you hear. Long waves have lower frequency and low pitch, short waves have high frequency and high pitch. Ex. Violin- short frequency and high pitch cello- low frequency and low pitch
How do we locate sounds?
Sound waves strike one ear sooner and more intensely than the other ear. The brain then analyzes the very minute differences in the sound received by both ears and determines the sound's source.
How does the ear transform sound energy into neural messages?
The pinna (visible outer ear) funnels sound waves through the auditory canal to the tempanic membrane (eardrum). The tempanic membrane vibrates and passes the vibrations of the three bones of the middle ear (malleus, incus, and stapes). These vibrations are transmitted from the stapes to the oval window on the cochlea (inner ear). These vibrations are transferred to the fluid in the cochlea causing the hair cell (neural cells) to move and send impulses to the auditory nerve. The auditory nerve sends neural messages (through the thalamus) to the temporal lobe's auditory cortex. Most hearing loss is due to damage of the hair cells. When sound exceeds 100 decibels it can permanently damage the hair cells. We perceive loudness by the number of hair cells that are stimulated. A hair cell can be damaged an unable to hear soft sound, but still be able to detect loud sounds.
How do we experience taste?
There are five taste sensations: sweet, salty, bitter, sour, and umami (meaty or savory). Biological, taste attracts us to "energy" rich foods that allow our survival (proteins, carbohydrates), and defer us from eating foods that might be toxic. This is potentially a reason that some young children are fussy eaters, not wanting to try some meats and bitter vegetables like spinach. Taste is chemical. Each bump on your tongue contains approximately 200 taste buds that contain a pore to catch food chemicals. These taste receptors replace themselves every week or two. Taste receptors are lost as we age, which is why taste sensitivity decreases with age. The loss of these receptors with age is also why adults enjoy stronger tasting foods than children. Individuals that have lost their sense of taste say food becomes difficult to eat because it tastes like straw. Our expectations of how something will taste also influences our response. If you are told that something will taste badly, your brain will register a stronger dislike than if you are not forewarned. People that are told that a particular food is more expensive ($100 caviar as opposed to $25) will often say the taste is better even if they have been lied to and the foods have been switched. Taste is also influenced by smell and texture. This is known as sensory interaction (one sense influencing another).
How do we sense touch and sense our body's position and movement? How do we experience pain?
Touch is a combination of several sense, pressure, warmth, cold , and pain. Pressure is the only sense that has identifiable receptors. If adjacent pressure points are stroked a tickle is felt. Continual gentle stroking of a pain spot causes an itching sensation. Touching adjacent cold and pressure spots triggers a sensation of wetness. Stimulating adjacent cold and warm spots produces a sensation of heat. Rubber-hand illusion p. 142 We sense position and movement through kinesthesis. A vestibular sense helps us maintain our balance and body's position. The semicircular canals (found in the inner ear) and the vestibular sacs ( connect the canals of the cochlea) contain fluid that moves when your head moves. This movement of fluid stimulates hair-like receptors, sending message of body position to the cerebellum. This helps you maintain balance. Read Ian Waterman's story on p. 142 Pain is a warning system that draws our attention to a physical problem. Nociceptors are receptors that help detect painful temperatures, pressures, or chemicals. Ronal Melzack and Patrick Wall proposed the gate-controlled theory to explain how pain is experienced. It states that the spinal cord contains a neurological "gate" that either blocks pain signals or allows them to pass on to the brain. The "gate" is opened by the activity of pain signals that travel up small nerve fibers and is closed by activity in larger fibers (that conduct most other sensory signals) or by information coming from the brain (distractions from pain {psychological influence} or natural painkillers {endorphins}). Humans feel, see, hear, taste, and smell with the brain. This is one reason individuals that have lost or are born without a limb can have phantom limb sensations, This also happens with hearing, vision, and taste. Psychological influences can affect how we feel pain. This is why athletes often finish a game; they are focused on winning, and then realize an injury. Humans also alter our memories of pain. The pain we actually experienced is different from the pain we experienced. Social-cultural influences also alter our perception of pain. We perceive more pain when others around us also seem to be experiencing pain.
. How adaptions is our ability to perceive?
We are able to adapt to changes in our visual field. Perceptual adaption is our ability to adjust to an artificially displaced or inverted fields. When individuals that wear glasses get a new prescription they often feel dizzy or strange for a few days until we adapt. People can even adapt if given glasses that shift the world to the right, left, or upside down.
What type of evidence shows that, indeed, " there is more to perception than meets the senses"?
We construct our perceptions based on both sensory input and-experiments show- on our assumptions, expectations, schemas, and perceptual sets, often influenced by the surrounding context.
How does our system for sensing smell differ from our sensory systems for vision, touch, and taste?
We have three types of color receptors, four basic touch senses, and five taste sensations. But we have no basic smell receptors. Instead, 1000 odor receptors, individually and in combination, recognize some 10,000 discernible odors.
Continuity
We percieve smooth, continuous patterns rather than discontinuous ones
Cochlea
a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
22. How do we perceive motion?
When objects are moving, we assume that objects getting smaller are retreating and objects getting larger are approaching. Our brain can be tricked into perceiving motion by creating "stroboscopic movement". Animation is created in this fashion (flashing 24 still pictures in a second). Marquees and holiday lights create an illusion of movement through blinking stationary lights. This is known as the phi phenomenon.
Although sound comes from speakers on the sides of the room, viewers watching a movie perceive the sound coming from the screen. This phenomenon is best accounted for by (A) visual capture (B) proximity (C) closure (D) opponent-processes (E) feature-detection
a
An object as it appears in the world as a visual stimulus is referred to as the (A) distal simulation (B) proximal stimulus (C) figure (D) ground (E) retinal image
a
On its way to the cones and rods of the eye, (in order) light passes through the (A) cornea, vitreous humor, lens, iris, aqueous humor (B) sclera, lens, pupil, iris, vitreous humor (C) cornea, aqueous humor, pupil, lens, vitreous humor (D) sclera, aqueous humor, lens, pupil, vitreous humor (E) retina, vitreous humor, lens, iris, aqueous humor, fovea
c
Our tendency to see faces in clouds and other ambiguous stimuli is partly based on (A) selective attention (B) ESP (C) Perceptual set (D) Shape constancy (E) Bottom-up processing
c
Signal detection theory is most closely associated with (A) vision (B) sensory adaptation (C) absolute threshold (D) hearing (E) context effects
c
Awareness, integration, and organization of information into meaningful information is known as (A) sensation (B) perception (C) illusions (D) false perception (E) convergence
b
Subliminal
below one's absolute thrshold for sonscious awareness
The Gestalt concept of perceptual continuity refers to (A) our tendency to see objects near to each other as belonging to the same group (B) our tendency to see objects that are closer to us as larger than objects that are farther away (C) our tendency to see fluid or complete forms rather than irregular or incomplete forms (D) our tendency to see similar-looking objects as part of the same group (E) our tendency to see two slightly different images from each of our eyes
c
A landscape painting shows boats on a lake in the foreground and mountains farther away. Of the following, which cue would not contribute to your perception that the mountains are farther away than the boats in the picture? (A) texture gradient (B) linear perspective (C) relative height (D) retinal disparity (E) interposition
d
Transduction
conversion of one form of energy into another. insensation, the transformming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret
Cells that can respond to specific edges, line, angles, and movements are called (A) rods (B) cones (C) ganglion cells (D) feature detections (E) bipolar cells
d
In the signal detection theory, when a participant responds that a stimulus was present and it was, the response is called a (A) Correct rejection (B) ROC curves (C) Miss (D) Hit (E) False positive
d
All sensory information is sent to the thalamus EXCEPT (A) taste (B) vision (C) audition (D) touch (E) smell
e
Laticia is listening to her teacher conduct a lesson on the parts and functions of the brain. Laticia can distinguish her teacher from the board because of which Gestalt principle? (A) proximity (B) closure (C) similarity (D) continuity (E) figure-ground
e
The order of the bones in the middle ear is (A) incus, malleaus, stapes (B) stapes, malleaus, incus (C) stapes, incus, malleaus (D) malleaus, stapes, incus (E) malleaus, incus, stapes
e
The part of the eye responsible for receiving photons of the light then translating them into neural messages is the (A) sclera (B) lens (C) cornea (D) pupil (E) retina
e
The point of focus for the eye that contains mostly cones is the (A) rods (B) iris (C) cones (D) retina (E) fovea
e
Sensorineural Hearing Loss
hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness
Conduction Hearing Loss
hearing loss caused by damage to the mechanical system that conducts sound waves the cochlea
subliminal stimulation
is below one's absolute threshold for conscious awareness. Subliminal messages have been used by advertisers to sell products or to help people break bad habits (smoking, over eating). This makes two assumptions about subliminal messages: 1) We can unconsciously sense them and 2) Without our awareness, these stimuli have extraordinary suggestive powers.
absolute threshold
is the minimum stimulation needed to detect a particular stimulus (light, pressure, sound, taste, odor) 50% of the time.
size constancy
objects closer to our eyes will produce bigger images on our retinas, but we take distance into account in our estimations of size. we keep a constant size in mind for an object(if we are fimilar with the typical size of the object) and know that it does not grow or shrink in size as it moves closer or farther away
Shape Constancy
objects viewed from different angles will produce different shapes on our retinas, but we know the shape of an object remains constant
Weber's Law
principle that, in order to be perceived as different, two stimuli mist differ by a constant proportion, not a constant amount. Ex. An object's weight must differ by 2% in order to reach difference threshold
Audition?
sense or act of hearing
Optic Nerve
the nerve that that carries neural impulses from the eye to the brain
Closure
we fill in the gaps to create a complete, whole object
Proximity
we group neary figures together
Similarity
we group similar figures together
brightness constancy
we percieve objects as being a constant color even as the light reflecting off the object changes
relative height
we percieve objects higher in our feild of vision as farther away
21. How do we see the world in three dimensions?
*Depth perception allows us to see the world in three dimensions and to be able to judge distances. Scientists study depth perception in infants (age 6 to 14 months) and young animals using a visual cliff (a device that tests depth perception in infants and young animals). The visual cliff is a large glass table. A portion of the table has a pattern under the glass so the infants or animals cannot see the ground. A cliff effect is created when the pattern portion ends and only glass remains, allowing the ground to be seen. Animals will not walk past the pattern portion, and infants will not crawl past the pattern portion (even with coaxing from the mothers) because by the time we are mobile we have the perceptual abilities necessary to keep us safe. *Binocular cues also play a role in three dimensional vision. Two eyes are literally better than one. The brain computes the distance between two images with information received from both retinas. This is known as retinal disparity. The greater the difference (disparity) between the two images, the CLOSER the object. To test this hold create a finger sausage by holding you two index fingers together in front of your nose. Now move them away and watch the sausage disappear. There is a greater disparity between your two retinas close up than there is when you move your fingers away (increase the distance). 3-d movies are created using this retinal disparity. Scene are filmed using two camera placed only a few inches apart. When you view the movie through the special glasses, the images seem to be 3 dimensional because the left lens of the glasses allow you to see the images from the left camera, and the right lens allow you to see the images from the right camera. This exaggerates the normal retinal disparity. *Monocular clues help us judge distances using information from only one eye. These clues influence our everyday perceptions. The following are monocular depth clues: (figure 4.38) ^Relative height- objects that our higher in our field of vision our perceived as being further away. ^Relative size- when we assume objects are similar in size, the object that casts a smaller retinal image is seen as farther away. ^Interposition- if one image blocks our view of another, we perceive the image (the one that is doing the blocking) as closer. ^Linear perspective- parallel lines (like railroad tracks) seem to converge (come together) with distance. The more they come together, the greater the perceived distance. ^Relative motion- while we are moving (like riding in a car) stationary objects seem to move. While riding if you and the objects in front of the barn seem to move backwards. ^Light and shadow- Objects nearby reflect more light. If you are looking at two identical images, the dimmer object (one with more shading) will seem farther away.
What is the rapid sequence of events that occurs when you see and recognize someone you know?
1. Light waves reflect off the person and travel to eye 2. Rods and cones convert the light waves' energy into neural impulses sent to brain 3. Brain processes the sub-dimensions of this visual input into a conscious perception of the person you know (including color, depth, movement, and form separately but simultaneously, and integrates this information along with previously stored information)
10. Vibrating molecules in the air are called a) light waves b) sound waves c) odor molecules d) taste sensations
10. b The outer and middle ear are designed to funnel the vibrating air molecules to the inner ear, where they are translated into an electrical signal and sent to the brain.
11. The membrane stretched over the opening to the middle ear is the a) pinna b) oval window c) tympanic membrane d) cochlea
11. c The tympanic membrane is also known as the eardrum. Sound waves cause the tympanic membrane to vibrate, which then causes the bones of the middle ear to move back and forth.
12. Which is the correct order of the three bones of the middle ear, from the outside in? a) anvil, hammer, stirrup b) hammer, anvil, stirrup c) stirrup, anvil, hammer d) stirrup, hammer, anvil
12. b The order of the bones is hammer, anvil, stirrup which spells "has."
13. Which theory proposes that above 100 Hz but below 1000Hz, auditory neurons do not fire all at once but in rotation? a) place theory b) volley theory c) frequency theory d) rotational theory
13. b Volley theory describes the perception of pitch for the middle frequencies (100 - 1000 Hz). Frequency theory describes the low frequencies (100 Hz and less) and place theory describes the fastest frequencies (1000 Hz and higher).
14. The _________ theory explains how we hear sounds above 1,000 Hz. a) place b) frequency c) volley d) adaptive
14. a The idea is that at very high sound frequencies, the action potential frequency can't keep up, so pitch has to be coded by the place on the basilar membrane that is activated.
15. Ringing or buzzing sensations in the ears may be a sign of: a) noise produced hearing damage b) habituation of the hair cells c) rigidity of the ossicles d) volley theory morbidity
15. a Damage to the hair cells can cause the receptors to fire action potentials even when no stimulus is present. This can cause a sensation of ringing in the ears.
16. _______________is the term used to refer to difficulties in hearing. a) Hearing impairment b) Timbre blindness c) Acoustic stiffness d) Volley involution
16. a Hearing impairments are usually divided into impairments of conduction and nerve.
17. If a severe ear infection damages the bones of the middle ear, you may develop _______ hearing impairedness. a) nerve b) stimulation c) brain pathway d) conduction
17. d Conduction hearing impairment is caused by damage to the outer or middle ear.
18. Cochlear implants bypass the: a) outer ear b) outer and middle ear c) outer, middle and inner ear d) none of the above
18. b Cochlear implants use an electronic device instead of the movements of the bones in the middle ear to convert the sound wave into a signal that is then sent to the auditory nerve in the inner ear.
19. The "bumps" on the tongue that are visible to the eye are the __________ a) olfactory receptors b) taste buds c) papillae d) taste receptors
19. c The bumps you can see with your eye are the papillae. The taste buds are located along the sides of the papillae. Each taste bud contains 10-20 taste receptors.
20. An olfactory stimulus travels from receptor to _____________. a) olfactory bulb b) thalamus c) amygdala d) pons
20. a The olfactory system is the only system in which the receptors send their signal directly to the higher brain and bypass the filtering process of the lower brain.
21. In gate control theory, Substance P a) opens the spinal gates for pain. b) closes the spinal gates for pain. c) is unrelated to pain. d) is similar in function to endorphins.
21. d The gate-theory of pain suggests that there are a number of factors in the central and peripheral nervous system that can inhibit or allow pain signals to be transmitted to the brain.
22. Which is the best description of the vestibular senses? a) having to do with touch, pressure, temperature, and pain b) having to do with the location of body parts in relation to the ground and to each other c) having to do with movement and body position d) having to do with your location as compared to the position of the sun
22. c The vestibular sense provides you with a sense of balance and sends your brain information about acceleration and tilt.
23. We know when we are moving up and down in an elevator because of the movement of tiny crystals in the a) outer ear b) inner ear c) otolith organs d) middle ear
23. c Although the otolith organs are located in the inner ear, choice c is a more precise answer.
24. Which might be the best explanation of motion sickness, according to your textbook? a) The conflict between vision and the vestibular organs b) Fluid circulating in the semicircular canals c) Human evolutionary history in that poisons make us dizzy, so when motion makes us dizzy we try to expel the poison d) none of these
24. c Although choice a is partially correct, the conflict between the visual and vestibular system only explains the sense of dizziness, not the sense of nausea. Probably the best explanation for that is human evolutionary theory.
25. The tendency to interpret an object as always being the same size, regardless of its distance from the viewer is known as _____________ a) size constancy b) shape constancy c) brightness constancy d) color constancy
25. a Size constancy refers to the fact that our perception of the size of an object tends to remain constant.
26. Closure is _________________ a) the tendency to perceive objects, or figures, on some background. b) the tendency to complete figures that are incomplete. c) the tendency to perceive objects that are close to each other as part of the same grouping. d) the tendency to perceive things a with a continuous pattern rather than with a complex, broken-up pattern.
26. b Closure is one of the Gestalt principles of perception and refers to our tendency to "close" objects to form a complete picture.
27. Which Gestalt principle is at work in the old phrase, "birds of a feather flock together?" a) closure b) similarity c) expectancy d) continuity
27. b The saying is emphasizing that objects with similar characteristics ("birds of a feather") tend to be grouped together ("flock together"). This is the principle of similarity
28. Visual distance and depth cues that require the use of both eyes are called ______. a) monocular cues b) diocular cues c) binocular cues d) dichromatic cues
28. c The phrase "ocular" means having to do with the eyes. "Mono" refers to one and "bi" refers to two. Therefore the term binocular means seeing depth with two eyes.
29. The Műller-Lyer illusion exists in cultures in which there are a) more men than women b) more women than men c) few buildings d) buildings with lots of corners
29. d The carpentered-world theory states that the Müller-Lyer illusion does not exist in certain "primitive" cultures because they are not surrounded by straight lines and corners.
3. An automobile manufacturer has decided to add a little bit of horsepower to its cars. They have a device that alters horsepower one unit at a time. Suppose drivers first notice the increase on a 200 horsepower car when it reaches 220 horsepower. How much horsepower must be added to a 150 horsepower car for drivers to notice the difference? a) 5 b) 10 c) 15 d) 25
3. c According to Weber's law, the just noticeable difference (jnd) is a constant proportion. A change from 200 to 220 represents an increase of 20 units and a jnd of 20/200 or 0.10, which is 10%. If the company starts with 150 horsepower, they will need to increase it by 10% in order for the driver to notice a difference. Ten percent of 150 is 15.
30. People's tendency to perceive things a certain way because their previous experiences or expectations influence them is called a) a perceptual set b) binocular disparity c) motion parallax d) accommodation
30. a An individual's expectations or perceptual set often influence perception of objects.
31. A recent review of studies on ESP using the Ganzfeld procedure concluded that ______. a) no convincing evidence for psychic ability had emerged from any of the studies b) no convincing evidence for psychic ability had emerged from the majority of studies c) convincing evidence for psychic ability had been found in the majority of studies d) convincing evidence for psychic ability had been found in virtually all studies
31. b The majority of quality studies have found no evidence for ESP. The studies that reported positive results have been flawed.
How many touch senses do we have
4
4. If you stared at a picture for a long period of time, you might think the image of the picture would fade due to sensory adaptation. This would be the case except for the tiny vibrations of your eye called: a) glissades b) saccades c) habituation movements d) light wave responses
4. b Saccades are the small quick movements your eye makes in order to keep the visual stimuli changing. When our sensory receptors receive unchanging, constant stimuli, they eventually stop responding to the stimulus. This process is known as sensory adaptation.
How many taste sensations do we have?
5
5. Light is said to have a dual nature, meaning it can be thought of in two different ways. These two ways are: a) particles and photons b) waves and frequencies c) photons and waves d) dark light and daylight
5. c Light can be thought of as a wave and as particles. Photons are the specific type of particles that light is composed of.
6. When light waves enter the eye, they first pass through the a) iris. b) lens. c) pupil. d) cornea.
6. d The cornea is the outermost coating of the eye. It is transparent and serves to protect the eye and to help focus the light coming into the eye.
7. Which of the following is true about cones? a) They are more sensitive to light than rods. b) They are found mainly in the center of the eye. c) They operate mainly at night. d) They respond only to black and white
7. b Cones are the sensory receptors that respond to color and send visual information of high acuity or visual sharpness. The cones are located primarily in the center of the retina. Choices a and d more accurately describe the rods.
8. The existence of afterimages in complementary colors best supports the ______ theory of color vision. a) opponent-process b) place c) vibrational d) Hering trichromatic
8. a The opponent process theory of color vision was introduced, in part, to explain the phenomenon of the afterimage
9. Which of the following properties of sound would be the most similar to the color or hue of light? a) pitch b) loudness c) purity d) timbre
9. a Pitch is determined by the length of the wave just as color is determined by the length of the wave. Both brightness and loudness are determined by the height of the wave.
What are the common causes of hearing loss, and why does controversy surround cochlear implants?
Conduction hearing loss is caused by damage to the mechanical system that conducts sound waves to the cochlea. Examples of conduction hear loss would be a perforated tympanic membrane or the inability of the three bones of the middle ear to vibrate. Sensorineural hearing loss is caused by damage to the cochlea's hair cells or to the auditory nerve. This is also known as nerve deafness. This is usually age related or caused by loud noises, but can also be caused by disease or accidents. A cochlear implant is a device for converting sound into electrical signals and stimulating the auditory nerve through electrode threaded into the cochlea (p.140). The implants are more frequently used to restore hearing, many deaf people believe they shouldn't be used (unnecessary) for those who have been deaf since birth since they can't speak using sign language. They also believe their other senses are enhanced.
What are the claims of ESP, and what have most research psychologists concluded after putting these claims to the test?
ESP is extrasensory perception, and half of all Americans believe humans are capable of it. There are three variations of ESP *Telepathy involves mind-to-mind communications *Clairvoyance involves perceiving remote events (sensing something is happening somewhere else) *Precognition involves perceiving future events Most research psychologists believe that perception isn't possible without sensory input. ESP has not been replicated under controlled conditions.
24. What does research on sensory deprivation and restored vision reveal about the effects of experience on perception?
People born blind (usually with congenital cataracts) that regain sight later in life lack the experience to recognize shapes, forms, and complete faces by sight. They are able to recognize these shapes, faces, and forms by touch, just not by sight. There is a critical period of time when some aspects of sensory and perceptual development are formed. If there is no neurological stimulation in the brain during this time, the neurons are unable to organize and develop properly. This explains why these individuals are unable to recognize these images visually. If a human's (or an animal's) visions restricted later in life, no permanent damage is done. If you covered a person's eyes for several months, and then removed the patches, their vision would be unaffected because the neural pathways were already formed.
Function of sensory adaptions
Sensory adaption is our diminished sensitivity to an unchanging stimulus. Ex. Stinky smell in a room, bracelet on your wrist Sensory adaption reduces our sensitivity and allows us to focus on information changes in our environment without being distracted by the constant uninformative background stimulation. If we stare at an object if doesn't disappear because on our eye continuously move and therefore continuously stimulate the nerve receptors. If you are fitted with a devise prevents that movement initially you would see an image, but overtime you would see fragments fading and reappearing.
Does sensory interaction affect hearing?
Sensory interaction does affect hearing. If we SEE someone making one syllable (like ga) while hearing another (like ba), we may perceive the word as da. This is known as the McGurk effect. Sensory interaction allows our brain to combine senses to help perceive sensations we normally we would be unable to. We might not be able to detect a slight flicker in a light, but if you combine the flicker with a loud sound and the neurons combine (sensory interaction) we become able to recognize the flicker. The brain blends the inputs. In some individual synaesthesia can occur because of sensory interaction. Synaesthesia occurs when one sensation (hearing) produces another (seeing colors).
20. How do figure-ground and grouping principles contribute to our perceptions?
To perceive objects (figures), the object must be able to be distinguished from its surrounding (the ground). This illustrates the figure- ground relationship. As you read these notes, the words are the figures and the white backdrop is the ground. Figure 4.32 shows a figure-ground drawing that continually reverses itself. The same stimulus is able to trigger more than one perception. Grouping occurs when our minds bring order and form to the stimuli it is receiving by following the rules of proximity, similarity, continuity, connectedness, and closure. Proximity occurs when we group nearby figures together. Ex. Six parallel lines perceived as three sets of double lines. Similarity occurs when we group similar object together. Ex. Perceiving triangles and circles in vertical columns, instead of horizontal lines of differing shapes. Continuity occurs when we perceive smooth, continuous patterns instead of discontinuous ones. Ex. Perceiving a wavy line with a straight line through it as just that, a wavy line and a straight line. Not perceiving it as alternating semi-circles around a straight line. Connectedness occurs when our brain tries to link uniform or linked spots, lines, or areas as a single unit. Closure occurs when we try to fill gaps to complete a whole object.
Assume you would like to look at the stars tonight. Since it is dark, you should try to use which cells in the eye to get a good look? (A) rods (B) cones (C) retina (D) fovea (E) periphery
a
Frequency theory relates to the (A) rate at which the basilar membrane vibrates (B) number of fibers in the auditory nerve (C) point at which the basilar membrane exhibits the most vibration (D) decibel level of a sound (E) number of hair cells in each cochlea
a
John complains that when he gets out of bed that he feels dizzy. He also says his ears hurt. Why is John commenting that his ears hurt? (A) The inner ear, specifically the semicircular canals and vestibular sacs, provide information for the vestibular sense, which monitors balance (B) The inner ear, specifically the hammer, anvil and stirrup, provide information for the vestibular sense, which monitors balance (C) The middle ear, specifically the semicircular canals and vestibular sacs, provide information to the vestibular sense, which monitors balance (D) The outer ear, specifically the semicircular canals and vestibular sacs, provide information to the kinesthetic sense, which monitors balance (E) The middle ear, specifically the semicircular canals and vestibular sacs, provide information to the kinesthetic sense, which monitors balance
a
Sensation refers to the (A) detection of stimulus energy from the environment (B) conversion of stimulus energy into neural code (C) organization and interpretation of stimulus energy (D) adaptation to an unchanging stimulus, resulting in diminished sensitivity (E) relaying of information that occurs in the brain
a
The _____________ is the first structure involved in focusing the photons of light. (A) cornea (B) lens (C) retina (D) sclera (E) vitreous humor
a
The part of the brain responsible for coding auditory information is the (A) temporal lobe (B) occipital lobe (C) somatosensory cortex (D) frontal lobe (E) hypothalamus
a
The two monocular depth cues that are most responsible for our ability to know that a jet flying high overhead is at an elevation of several miles are relative size and (A) relative motion (B) retinal disparity (C) interposition (D) light and shadow (E) linear perspective
a
When food supplies may be unsafe, which of the following would have an adaptive advantage over most other people? I. supertasters II. average tasters III. nontasters (A) I only (B) II only (C) III only (D) I and III only (E) I, II, III
a
Which of the following would be most difficult for a person who only had one eye? (A) inserting a toothpick into a horizontal straw (B) watching a movie at a theatre (C) correctly identifying the color of a car (D) organizing objects into similar patterns or colors (E) understanding that a line continues despite a break in it
a
Which of the following would be the best illustration of Weber's law? (A) As sound increases to 80 decibels from 40 decibels, most peoples can recognize that one sound is louder than the other. However, if the two sounds are given at 80 and 82 decibels respectively, most people would not recognize the difference between the two sounds. (B) A person can recognize an imperceptible amount of perfume in a ten foot-by-ten-foot room. (C) People cannot attend to more then one stimulus at a time. (D) A person has the ability to tell the difference between a 20 watt bulb and a 100 watt bulb 50 percent of the time. (E) All auditory stimuli above a certain frequency "sound" as if their frequencies are the same.
a
Retinal Disparity
a binocular cue for perceiving depth; by comparing images from the retinas in the two eyes, the brain computes distance- the greater the disparity(difference) betwenn the two images, the closer the object
Visual Cliff
a labortory device for testing depth perception in infants and young animals
Perceptual Set
a mental predisposition to percieve one thing and not another
Iris
a ring of muscles tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
Signal Detection Theory
a theory predicting how and when we detect the presence of a fainty stimulus(signal) ami background stimulation(noise). assumes there is no single absolute thershold and that detect depends partly on a person's experience, expectations, motivation, an alertness
Pitch
a tone's experineced highness or lowness; depends on frequency
How are we affected by selective attention?
attend to, and process, an extremely small amount of incoming information, while blocking out most of the other information. We also shift our focus (attention) from one thing to another during this process. you attention is focused elsewhere, you often exhibit inattentional blindness. Inattentional blindness is failing to see visible objects when our attention is directed elsewhere. Ex Basketball video Change blindness is another form of inattentional blindness that occurs when individuals fail to notice changes in their environment.
A cue used to understand distance is (A) pragnanz (B) linear perspective (C) Ponzo illusion (D) Good continuation (E) Proximity
b
According to the Gestalt principle of proximity (A) objects that display the same features are grouped together (B) objects that are close together are interpreted as belonging together (C) monocular cues allow the size of an object to remain constant (D) binocular cues allow the color of an object to remain constant (E) objects that are farther away look as if they are moving more slowly than do closer objects
b
Armando was tearing up old papers when he realized that he had accidentally torn up the homework that was due the next day. Because Armando knew what his homework was he was able to put the pieces back together with relative ease. Armando used which organizational strategy to reconstruct his homework? (A) Bottom-up processing (B) Top-down processing (C) Similarity processing (D) Perceptual blindness (E) The cocktail-party effect
b
Carlos was just able to perceive a difference in weight when Maria removed two of the 50 jelly beans from his plastic bag. It is most likely that if Carlos had the jumbo bag of 100 jelly beans, the smallest number of jelly beans he could notice removed would be (A) 2 (B) 4 (C) 8 (D) 16 (E) 20
b
Conventional hearing aids may restore hearing by (A) restoring functionality to a badly punctured eardrum (B) amplifying vibrations conducted by facial bones to the cochlea (C) translating sounds into electrical signals wired into the cochlea's nerves (D) stimulating the semicircular canals to transduce sound waves (E) converting sound waves to radio waves
b
Receptors for kinesthesis are located in the (A) retina (B) joints (C) semicircular canals (D) olfactory epithelium (E) taste buds
b
The ______________ carry information from the rods and cones back out to the ganglion cells and then out the brain. (A) Amacrine cells (B) Bipolar cells (C) Optic nerve (D) Occipital lobe (E) Temporal lobe
b
The four basic gustatory sensations that most animals possess are (A) bitter, salty, tangy, sour (B) salty, sweet, bitter, sour (C) smooth, grainy, cold, hot (D) grain, fruit, meat, vegetable (E) salty, sharp, sour, bitter
b
The part of the ear responsible for translating information into neural impulses is the (A) pinna (B) cochlea (C) semicircular canals (D) tympanic membrane (E) incus
b
The part of the eye responsible for opening and closing to allow in more or less light is the (A) sclera (B) pupil (C) lens (D) retina (E) cornea
b
The receptor cells that make the transduction for the auditory system are called the (A) basilar membrane (B) hair cells (C) cochlea (D) semicircular canals (E) stapes
b
When physical energy is transformed into neural impulses, it is referred to as (A) reception. (B) transduction. (C) perception. (D) sensation. (E) induction.
b
Which of the following is most likely to influence our memory in a painful event? (A) The overall length of the event (B) The intensity of pain at the end of the event (C) The reason for the pain (D) The amount of rest you've had in the 24 hours preceding the event (E) The specific part of the body that experiences the pain
b
Which of the following phrases describes top-down processing? (A). the entry level data captured by our various sensory systems (B). the effect that our experiences and expectations have on perception (C). our tendency to scan a visual field from top to bottom (D). our inclination to follow a predetermined set of steps, beginning with step 1, to process sound (E). the fact that information is processed by the higher regions of the brain before it reaches lower brain
b
Which sense is least involved in enabling you to maintain your balance when you stand on one foot? (A) kinesthesis (B) olfaction (C) vision (D) vestibular sense (E) somatosensation
b
Of the following, which bend incoming light rays to focus an image on the retina? I. cornea II. iris III. lens (A) I only (B) II only (C) III only (D) I and III only (E) I, II, III
d
Connectedness
because they are uniform and linked, we percieve each set of two dots and the line between them as a single unit
Devin understands that when a door is opening it does not lose its original shape. This is known as (A) perceptual ability (B) inattentional blindness (C) constancy (D) proximity (E) closure
c
Mechanical energy of vibrations is transduced to the electrochemical energy of neural impulses at the (A) retina (B) lens (C) cochlea (D) olfactory mucosa (E) taste buds
c
Of the following, which is not a basic taste? (A) sweet (B) salty (C) peppery (D) bitter (E) sour
c
The Gestalt psychologists were interested in (A) depth perception and how it allows us to survive in the world (B) why we see an object near us as closer rather than larger (C) how an organized whole is formed out of its component pieces (D) what the smallest units of perception are (E) the similarities between shape constancy and size constancy
c
The ability to talk on the phone and type on the computer at the same time is the result of (A) bottom-up processing (B) perceptual processing (C) selective attention (D) closure (E) convergence
c
The amount of a stimulus required to determine that a stimulus has changed just a little bit is called the (A) difference threshold (B) absolute threshold (C) just noticeable difference (D) just noticeable threshold (E) taste aversion
c
The cells responsible for coding for color in the eye are the (A) rods (B) iris (C) cones (D) retina (E) fovea
c
The optic chiasm is (A) responsible for color vision (B) where the optic nerve leaves the eye, causing a blind spot (C) where the optic nerves cross over to report information to opposite sides of the brain (D) where information from rods and cones is passed to the ganglion cells (E) responsible for detecting fine details
c
The purpose of the pupil is to (A) focus light on the retina (B) process color (C) allow light into the eye (D) enable night vision (E) detect specific shapes
c
The structure of the eye that changes shape to accommodate the closeness or distance of an object is the (A) cornea (B) retina (C) lens (D) sclera (E) iris
c
When Sue first went outside she found the cold unbearable. She complained how cold it was, but after a while the temperature did not seem to bother her. Which sensational process allowed Sue to tolerate the cold? (A) transduction (B) selective attention (C) sensory adaptation (D) accommodation (E) perceptual set
c
When a fortune teller claims to have the ability to see what the person you will meet and marry 10 years from now will look like, the person is professing to possess the ability of (A) telepathy (B) clairvoyance (C) precognition (D) telekinesis (E) top-down processing
c
Which of the following might result from a disruption of your vestibular sense? (A) inability to detect the position of your arm without looking at it (B) loss of the ability to detect bitter tastes (C) dizziness and a loss of balance (D) an inability to detect pain (E) loss of color vision
c
Which of the following represents perceptual constancy? (A) We recognize the taste of McDonald's food each time we eat it. (B) In the photos with people, the people almost always are perceived as figure and everything else as ground. (C) We know that the brightness of a printed page has not changed as it moves from sunlight to shadow. (D) From the time they are very young, most people can recognize the smell of a dentist's office. (E) The cold water in a lake doesn't seem so cold after you have been swimming in it for a few minutes.
c
All except one of the following demonstrate a difference threshold. The exception represents an absolute threshold. Which of the following represents an absolute threshold? (A) a guitar player knows that his D string has just gone out of tune (B) a photographer can tell that the natural light available for a photograph has just faded slightly (C) your friends amazes you by correctly identifying unlabeled glasses of Coke and Pepsi (D) a cook can just barely taste the salt she has added to her soup (E) your mom throws out the milk because she says the taste is "off"
d
Cats tend to notice slight movements under low lightening conditions with greater ease than do humans; they do not, however, find it easy to distinguish colors. This is primarily due to their retinas containing, in comparison to humans (A) relatively fewer numbers of amarcine cells and relatively more bipolar cells (B) relatively fewer numbers of ganglion cells and relatively more osmoreceptors (C) Relatively fewer numbers of cilia and relatively more optic nerve cells (D) Relatively fewer numbers of cones and relatively more rods (E) Relatively fewer numbers of mechanoreceptors and relatively more ossicles
d
Neural impulses go directly to the cortex without passing through the thalamus from receptors in the (A) retina (B) joints (C) cochlea (D) olfactory epithelium (E) taste buds
d
Study subjects were placed in a darkened room and told to focus on a single stationary point of light on the wall. After a few minutes subjects reported that the point of light was moving. This apparent movement is known as (A) phi phenomenon (B) the Gestalt law of proximity (C) stroboscopic motion (D) the autokinetic effect (E) perceptual constancy
d
The hammer, anvil, and stirrup (A) process only high frequency sounds (B) process only low frequency sounds (C) make up a frame that supports the eardrum (D) transmit sound waves to the cochlea (E) hold the hair cells that enable hearing
d
The height of a sound wave determines the (A) pitch (B) frequency (C) timbre (D) loudness (E) transduction
d
The part of the brain responsible for coding visual information is the (A) temporal lobe (B) somatosensory cortex (C) hypothalamus (D) occipital lobe (E) frontal lobe
d
Which of the following is NOT an example of a monocular visual depth perception cue? (A) Texture gradient (B) Motion parallax (C) Interposition (D) Opponent process (E) Relative size
d
_________ are the receptor cells for audition and _________ are the receptor cells for vision. (A) olfactory cells; rods and cones (B) taste buds; rods and cones (C) rods and cones; hair cells (D) hair cells; rods and cones (E) proprioceptors; rods and cones
d
Monocular Cues
depth cues, such as interposition and lineaqr perspective, available to either eye alone
Binocular Cues
depth cues, such as retinal desparity, that depend on the use of two eyes
Sensory Adaptation
diminished sensitivity as a consequence of constant stimulation
The structure that contains the main receptor cells in the auditory system is the (A) semicircular canals (B) tympanic membrane (C) pinna (D) malleaus (E) cochlea
e
The theory that best accounts for the experience of pain is (A) the opponent-process theory (B) Weber's law (C) The trichromatic theory (D) The direct perception theory (E) The gate-control theory
e
Which of the following is not a Gestalt grouping principle? (A) proximity (B) similarity (C) closure (D) continuity (E) figure-ground
e
Your tendency to see the words "went" and "ties," rather than the word "twenties" when you look at T WENT TIES is best explained by the organizing principle of (A) bottom-up processing (B) closure (C) continuity (D) figure-ground (E) proximity
e
Change Blindness
failing to notice changes in the enviroment
Inattentional Blindness
failing to see visible objects when our attention is directed elsewhere
What is the pathway from the eyes to the visual cortex?
ganglion axons forming the optic nerve run to the thalamus, where they synapse with neurons that run to the visual cortex
interposition
if one object particularly blocks our view of another, we percieve it as closer
relative size
if we assume two objects are similar in size, most people percieve the one that casts the smaller retinal image as farther away
Frequency Theory
in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tine, thus enabling us to sense its pitch
Place Theory
in hearing, the theroy that links the pitch we hear with the place where the cochlea's membrane is stimulated
Perceptual Adaptation
in vision, the ability to adjust to an artifically displaced or even inverted visual field
Top-Down Processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experinece and expectations
Difference threshold
minimum difference between two stimuli required for detection 50% of the time. We experience the difference threshold as a just noticeable difference (jnd). Ex. Add 1lb to 10lb and you could tell the difference. Add 1lb to 100lb and you probably wouldn't be able to tell the difference.
Feature Detectors
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
In our everyday experiences, sensation and perception are different aspects of..?
one continuous process
linear perspective
parallel lines, such as railroad tracks, appear to converge with distance. the more they converge, the greater their percieved distance
Color Constancy
percieving familiar objects as having consistent color, even if changing illumination alters the wavelenghths reflected by the object
Perceptual Constancy
percieving obkects as unchanging (having consistent shapes, size, lightness, and color) even as illumination and retinal images change
Middle Ear
the chamber between the eardrum and cochlea containg three tiny bones(hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochleas oval window
Intensity
the amount of energy in a light or sound wave, which we percieve as brightness or loudness, as determined by the wave's amplitude
Fovea
the central focal point in the retinal, around which the eyes cones cluster
What theories help us understand color vision?
• Humans can normally detect 7 million different color variations (except individuals with colorblindness). • The Young-Helmhotz trichromatic (3 color) theory explains how we can see various colors. It states the retina has three types of color receptors, each sensitive to one of three colors (red, green, blue). Stimulation combinations of these cones help us to see color (seeing yellow is because read and green cones are stimulated). People that are colorblind have particular cones that don't function properly (usually red or green.) • The opponent-process theory helps us understand how we see color through afterimages. Red-green, tallow-blue, and white-black are the three sets of opposing colors. It explains that we see a color by turning some neurons on and others off, some cells are stimulated by red and turned off by green or vis versa.
How the eye transforms light energy into neural messages?
• Light enters the eye through eh cornea (protects eye and focuses light). • Light passes through the pupil (adjustable opening in the iris). • The iris dilates or contracts based on light intensity or emotions. • The lens is found behind the iris and focuses the light onto the retina. The lens focuses the light by accommodation (changing the curvature of the lens). • The retina is a multilayered tissue on the inner surface of the eye. • The retina contains rods and cones (nerve receptor cells). Cones are found near the center of the retina and detects color, fine detail, and operate in light conditions. Rods are concentrated on the periphery of the retina and detect black, white, and gray and aid in the peripheral and low-light vision. • The optic nerve carries all the information to the thalamus of the brain where the information is then distributed. Where the optic nerve leaves the eye we have a blind spot because there are no receptor cells in the area. • The fovea is the retina's area of central focus because the cones cluster in and around the fovea. It is true that images are inverted on the retina, but we perceive the image as right side up because the retina doesn't see a whole image. The millions of receptor cells convert the light particles into neural impulses and send them to the brain where they are reassembled into an upright image.
How does the brain process visual information?
• The retina is made up of neural layers, which are brain tissue that migrates to the eye during early fatal development. These layers pass electrical impulses to the brain as well as encoding and analyzing data. • The 130 million receptor cells (rods and cones) process information, sending it your bipolar cells, then your ganglion cells, then through the ptic nerve (made up of the axons of the ganglion cells), to the thalamus (in the brain), and to the visual cortex (occipital lobe). • Feature detectors are nerve cells in the visual cortex of the occipital lobe that respond of specific features of the stimulus, like shapes, angles, or movement. • Feature detectors pass information to the other cortical areas where supercell clusters respond to the patterns. An area of your temporal lobe (behind right ear) allows you to see faces. If this area is damages you can recognize other objects, but not faces. A functional MRI can determine the object a person is looking at by the area of the brain that is stimulated. • Our brain processes many forms of information at once, parallel processing. It is able to divide a visual scene into sub-dimension (like color, movement, form, and depth) and work on each one simultaneously. • For you to recognize your fiend's face, the brain integrates the information sent from the retina to several areas in the visual cortex, compares these to stored information, and enables you to recognize the face.
