PSYCH 107 Exam #2 Review
Sensation and Perception
1) What is sensation?
a. The sense organ’s detection of external stimuli, their responses to the stimuli, and the
transmission of these responses to the brain
2) What is perception?
a. The processing, organization, and interpretation of sensory signals, it results in an
internal representation of the stimulus
3) What is psychophysics?
a. A subfield developed in the 19 century by Ernst Weber and Gustav Fechner that
examines our psychological experiences of physical stimuli
b. Ex. How much energy is required for our organs to detect a stimulus
4) What is the absolute threshold? Difference Threshold?
a. Absolute: minimum intensity of stimulation that must occur before you experience
b. Difference: just noticeable difference between two stimuli
5) What is signal detection theory? What is hit, miss, false alarm, and correct rejection? What is
a. Detecting a stimulus requires making a judgment about its presence or absence, based
on subjective interpretation of ambiguous information (green and swets, 1966), it is not
an all-or-none process
b. Hit- signal is presented and the participant detects it
c. Miss- participant fails to detect the signal
d. False alarm- participant “detects” a signal that was not presented
e. Correct rejection- no signal presented, and no detection by participant
f. Response bias- participant’s tendency to report detecting the signal in an ambiguous
trial. Ex. Does not want to respond and needs a lot of stimulus to say they felt it.
6) What is sensory adaption?
a. A decrease in sensitivity to a constant level of stimulation
i. Ex. Not hearing ongoing construction over time
7) What are the six senses?
a. Taste (gustation), smell (olfactory), touch (haptic), hearing (auditory), sight (vision), and
kinesthetic/vestibular sense (voluntary movement, positions in space, etc.)
8) What is transduction?
a. A process by which sensory receptors produce neural impulses when they receive
physical or chemical stimuli
9) For each of the following five senses: vision, auditory, olfactory, gustatory, and touch, be able to
describe the process by which the brain senses that type of information, including detail for
each sense, including differences for taste (ex. Sour, sweet), smells, touch sensations, auditory
information, and what parts of the brain each type of info is sent to. a. Taste- taste buds on tongue/mouth/throat are stimulated and signals are sent to the
brain. Different kinds of taste buds that taste each of the five tastes are spread
b. Smell- nasal cavity gathers odorants and comes into contact with odorant molecules,
the olfactory epithelium; it goes to the olfactory bulb (the brain center for smell). The
prefrontal cortex determines if a smell is pleasant or not. Different receptors are
sensitive to different smells
c. Touch- tactile stimulation comes from contact with our skin. Sensory neurons to the
outer layer detect temperature and pressure. Signals enter the CNS and to the brain.
Hot and cold sensation at once can produce a false feeling of wetness, for example.
Stroking multiple pressure points is pleasant or unpleasant (tickling) depending on the
d. Hearing- a sound wave moves through the ear canal and vibrates the eardrum.
Vibrations move the ossicles and then to the oval window in the inner ear’s cochlea. The
basilar membrane moves and bends hair cells, which send information to the auditory
nerve, then to the brain. Amplitude of a sound wave determines its loudness, frequency
determines its pitch
e. Sight- light passes through the cornea and is focused and forms an image on the retina
in the back of the eye. The retina has photoreceptors, photopigments, which transduce
light into neural signals. Rods are for night vision, no color or fine detail. Cones are for
color and detail. Bipolar, amacrine, and horizontal cells converge on ganglion cells which
are the first neurons in visual pathways with axons, first to generate action potential
10) What is a supertaster? What are examples of how taste shifts with age? Why does this occur?
a. Supertaster- highly aware of textures and flavors and are more likely to feel pain from
b. How/why does taste shift with age? Taste is based on our brains perception, taste
receptors can be lost, culture shifts taste preferences, medicines change taste
preferences, we like sweeter foods when we are younger
11) With respect to the sense of touch, how quickly do myelinated fibers send information that you
are sensing pain? How quickly do non-myelinated fibers send information? Why does the body
send pain information at two different “speeds”?
a. Myelinated- “fast fibers” sharp, immediate pain
b. Nonmyelinated- “slow fibers” chronic, dull, steady pain
c. Fast acting speed is when something needs to be alerted to your body very quickly,
protective to recoil from harmful objects
d. Slow acting speed is protective to prevent us from using hurt parts of our body, helps in
12) What is the gate-control theory of pain? What kinds of information can distract you from pain
a. Developed by Melzack and Wall; spinal cord contains a “gate” which opens and closes to
allow or block pain signals from traveling to the brain. Pain moves to brain when it is along the small nerve fibers, but does not when it is on the large; no physical stimulus is
actually needed- ex. Phantom limb pain
b. Hot or cold packs, talking, pain elsewhere in the body, visualize pain as a positive,
listening to music, medicines, etc.
13) With respect to the sense of hearing, how can people distinguish in differences in loudness of
sounds? Pitch of sounds?
a. The amplitude of a sound wave entering the ear determines its loudness
b. The frequency of a sound wave determines its pitch
14) With respect to sense of hearing, how do we locate where a sound is coming from?
a. We judge which eardrum receives the information first
15) With respect to sight, what is the blind spot?
a. The area in the back of the eye where the optic nerve exits the eye at the back of the
retina; cannot see
16) With respect to sight, what are rods and cones? Where are they located? What are they
specialized to detect? Which way are they facing the eye? Where are they located with respect
to the retina?
a. Rods and cones transduce the light into electrical signals with the help of
b. They are located in the retina
c. Rods detect dim light, no color, no fine detail; cones detect color and fine detail
d. They face the back of the eye
e. Cones are densely packed in the fovea, and diminish significantly towards the outside of
the retina; rods are concentrated at the retina’s edges
17) What is the trichromatic theory of how we distinguish different colors? What are strengths and
weaknesses of this theory?
a. Color vision results in activity from three different types of cones that are sensitive to
different wavelengths. One sensitive to short wavelengths (Blue-violet light), one to
medium (yellow-green), and one to long (red-orange). The cones are called, S, M, or L
due to that.
b. Strengths- the brain can’t tell the difference between yellow and equal amounts of red
and green. SML cones
c. Weakness- does not explain our difficulty with visualizing certain color mixtures. Hard to
18) What is the opponent-process theory of how we distinguish different colors? What are
strengths and weaknesses of this theory?
a. Herring in 1878/1964; “opposites” such as staring at a green dot and seeing a red
afterimage when we look away; determined by excited ganglion cells
b. Strengths- explains why we see opposite colors
c. Weaknesses- one cone fires upon seeing red/green
19) What is the dual process theory of how we distinguish different colors? What are strengths and
weaknesses of this theory? How does it differ from the opponent-process?
a. Theory- explains why we see the after image; empirically supportive b. Strengths- why we see green and red; one cone fires after seeing red, the other after
green, but ganglion cells send a message to red after seeing and firing green, telling the
red not to fire
20) What is subtractive color mixing? Additive color mixing?
a. Subtractive- mixture occurs within the stimulus and is a physical process, ex. mixing
paints. Pigment is determined by the wavelength that is not absorbed. Red, yellow,
blue= subtractive primary colors ex. A blue shirt only reflects short blue wavelengths, so
that is what you see
b. Additive- wavelengths are mixed and the interaction of them with the eye’s receptors
produces what you see. Ex. Stage lighting. Red, green, and blue= additive primary colors
21) What is the Gestalt principle of proximity? Similarity? Continuation? Closure?
a. Proximity- the closer two figures are to each other, the more likely we will group them
and see them as part of the same object
b. Similarity- “one of these things is not like the other”; we group things based on how
alike they are in size, shape, color, etc.
c. Continuation- interpreting lines as continuous versus ones that change direction
d. Closure- tendency to complete figures with gaps, such as a triangle with a piece of a side
22) What is the principle of figure-ground relations?
a. You never see both images at the same time, ex. Vase OR two faces because the brain
chooses a figure and puts the rest in the background
23) What is “top-down” processing? (vs. “bottom-up”)
a. Top-down- info at higher processing levels influences lower, “earlier” levels.
b. Bottom-up is lower to higher. Ex. The cat, when the h and a look the same you must
really think and sound out the words
24) Describe how all of the following molecular cues help us judge depth and distance: linear
perspective, occlusion, familiar size, relative size, texture gradient, position relative to horizon.
Be able to recognize examples of each.
a. Linear perspective- seemingly parallel lines appear to converge in the distance
b. Occlusion- a near object occludes (blocks) a far away object
c. Familiar size- we know how large familiar objects are so we can tell how far away they
are by the size of their retinal images
d. Relative size-far objects project a smaller retinal image than close objects do, is the
close and far objects are the same physical size
e. Texture gradient- as a uniformly textured surface recedes, its texture continuously
f. Positions relative to horizon- objects below the horizon, higher in the visual field, appear
far away. Objects higher than the horizon, lower in the visual field, appear far away.
25) What is retinal disparity? Convergence? a. Retinal disparity- marks the difference between two images. Because the retinas are a
few inches apart, they pick up slightly different images. It increases as the eyes get
closer to an object
b. Convergence- eyes turn inward to look at an object close up, the closer an object is, the
more the muscles more. The muscles send signals to the brain to determine how close
the object is
26) How does the Ames room work?
a. 1940s, Albert Ames, differing depth cues, but the eye only recognizes the size of the
child inside that appears to change. The room is built like an irregular 3-D trapezoid. The
length of one wall may be 12ft. and the opposite, 7ft. the height of one side of the
ceiling may be 8ft. and slope down to 5ft at the other side.
27) What is the Ponzo illusion?
a. Mario Ponzo (1913); 2-d figures can seem 3-d, brain uses depth cues even when there is
not any depth. Two lines seem to be different sizes because of the way lines around
28) How did V.S. Ramachandran help patients who suffered from phantom limb pain?
a. He gave them a box with a mirror so they could look at a reflection of their other limb
and pretend the reflection is the missing limb. It tricked their body so they were able to
relieve the phantom pain; it created an illusion of kinesthetic sense of movement and
motion to reduce the pain
29) What are motion aftereffects?
a. Gazing at a moving image for a long time and when you look away to a stationary image,
you feel it is still moving the opposite direction of the moving image…”waterfall effect”
because if you stare at a waterfall and then look away, everything will appear to move
upwards for a moment
30) Why is it that every time you move your eyes or your head, you don’t perceive anything in your
sight to be jumping around? In other words, why so you experience/perceive those objects as
a. The brain may calculate an object’s perceived movements based on eye movement,
motion detectors track an images motion across the retina
31) What is stroboscopic motion perception?
a. Our view that things are moving or linked together or shown at the same time when
two different images are flashed very quickly, one right after the other ex. movies
32) What role does culture play in perception?
a. Perception comes from our brains, which are shaped by our experiences and
interactions- our culture Learning and Reward
1) How does behaviorism differ from psychological studies of consciousness or cognition?
2) What is learning?
a. A relatively enduring change in behavior, resulting from experience
3) What is classical conditioning? What are the US, UR, CS, and CR? Be able to describe the process
of classical conditioning.
a. Pavlovian conditioning- a type of learned response; a neutral object comes to elicit a
response when it is associated with a stimulus that already produces that response
b. US- unconditioned stimulus; a stimulus that elicits a response, such as a reflex, without
any prior learning
c. UR- unconditioned response; a response that does not have to be learned, such as a
d. CS- conditioned stimulus; a stimulus that elicits a response only after learning has taken
e. CR- conditioned response; a response to a conditioned stimulus; a response that has
f. Dogs salivate when they see their food. A bell is rung when given their food. They
salivate (UR) when they see their food (US) and hear the bell. Soon they just salivate
(CR) when they hear the bell (CS).
4) What is extinction?
a. A process in which the conditioned response is weakened when the conditioned
stimulus is repeated without the unconditioned stimulus
5) What is spontaneous recovery?
a. A process in which a previously extinguished response reemerges after the presentation
of the conditioned stimulus
6) What is generalization?
a. Learning that occurs when stimuli that are similar but not identical to the conditioned
stimulus produce the conditioned response
i. Ex. Different tones of bells
7) What is discrimination (in the context of classical conditioning)?
a. A differentiation between two stimuli when only one of them is consistently associated
with the unconditioned stimulus
i. Ex. Different Shades of Grey slides shown to dogs
8) What is second-order (higher-order) conditioning?
a. The conditioned stimulus becomes associated with other stimuli associated with the
9) According to behaviorists, what is a phobia? How do people acquire phobias? How would you
cure a phobia based on principles of classical conditioning?
a. And acquired fear out of proportion to the real threat of an objector of a situation
b. They develop through a generalization of a fear experience. Ex. A wasp sting causes the
person to be afraid of all flying insects c. The scary object with more pleasant things, like candy. Give small doses of the fear
while doing an enjoyable task
10) Who was Baby Albert? What did the study involving baby Albert demonstrate with respect to
behaviorism? With respect to ethics in research?
a. He was a baby that Watson conditioned to be scared of rats, and later was scared of all
furry white things. Watson intended to then condition him out of his fear, but his mom
removed him from the study before that was possible
b. It showed that your behaviors are shaped based on your experiences.
c. It was viewed as highly unethical.
11) What is biological preparedness?
a. By Martin Seligman (1970), animals are genetically programmed to fear certain objects.
Ex. Animals fear heights and snakes but not flowers or the ground
12) What is the Garcia Effect?
a. We can develop conditioned taste aversion, coming from foods we may have been
nauseous from, even if we were sick and the nauseous feeling was not caused by the
food, but instead the illness; biologically prepared learning- avoiding things like posion
13) What does it mean that classical conditioning is a relatively passive form of learning, especially
compared to operant conditioning?
a. The person/animal did not have to perform and action to relate the stimulus and
response to each other. They occur without what the animal does beyond the stimulus
14) What is positive reinforcement? Positive punishment? Negative reinforcement and negative
punishment? You should be able to recognize examples of each.
a. Positive reinforcement- increases the chance a behavior will be repeated; “reward”;
adding something positive into the environment; ex. Increase in pay
b. Positive punishment- decreases the chance a behavior will happen again; adds