Exam 2 - Psych 100

sensation

detecting physical energy with our sense organs (eyes, ears, skin, nose, tongue)

perception

the brain’s interpretation of raw sensory information

illusion

the way we perceive a stimulus doesn’t match its physical reality

Transduction

conversion of an external stimulus into a neural signal

sensory receptors

specialized cells designed to convert a certain kind of external information into a neural signal

sensory adaptation

sensory neurons adjust their sensitivity based on recent stimulus history (ex: perceiving smells, adjusting to dark vs. light conditions)

aftereffects

opposing sensory or perceptual distortions that occur after adaptation

stimulus → interpretation

physical stimulus, transduction by receptors, signal carried to brain, goes through thalamus, arrives at appropriate location in cortex

Amplitude

how big high/short the waves are, how loud

frequency

how many waves there are, pitches

waves

sound and light

psychophysics

study of how our sensations (psychological events) correspond to physical events in the world

absolute threshold

lowest level of a stimulus needed for the nervous system to detect a change (50%) of the time

Just Noticeable difference (JND)

smallest change in the intensity of a stimulus that we can detect

Weber’s law

the stronger the stimulus, the bigger the change needed to detect it

signal detection theory

how stimuli are detected under different conditions

signal

what you are trying to detect

noise

similar stimuli that might compete with the signal and interfere with your ability to detect the signal

response criterion

operator’s bias towards perceiving a target signal from the background noise

Dichotic listening

play different information through each ear of headphones (information reported only from the attended ear

inattentional blindness

occurs when unattended stimuli are ignored as if they weren’t there

change blindness

a version of this that occurs when you fail to detect obvious changes in your environment

bottom-up processing

constructing a representation from parts and basic features

top-down processing

processing influenced by precious experience and knowledge

sensation

bottom-up process

perception

both bottom-up and top-down processing

perceptual sets

set formed when our expectations influence our perceptions

sclera

white part of your eye

pupil

circular hole where light enters in your eey

iris

colored portion of the eye that controls pupil size (letting in more or less light)

cornea

curved, transparent layer covering the iris and pupil that helps focus light

lens

oval shaped disc that bends light

accommodation

changing of the lens’ shape to focus on near/far objects

myopia (nearsightedness)

eye is too long

hyperopia (farsightedness)

eye is too short

retina

membrane at the back of eye responsible for converting light into a neural signal

fovea

central portion of the retina, responsible for visual acuity

acuity

sharpness of vision

saccades

small jerky movements of the eye allowing for rapid changes of focus

rods

respond under low levels of light, NOT color sensitive, outside of fovea

cones

sensitive to find detail, color sensitive, located in fovea, less plentiful than rods

optic nerve

bundle of axons that travels from the retina to the brain

blind spot

area of the retina where the optic nerve exits the eye

hue

color of light corresponds to wavelength

trichromatic theory

color vision is based on three primary colors (blue, green, red)

opponent process theory

we perceive colors in terms of three pairs of opponent colors:

red-green

blue-yellow

black-white

color blindness

inability to see some or al colors (loss of 1+ cones)

depth perception

ability to judge distance and spatial relations (depends on binocular depth cues and monocular depth cues)

binocular depth cues

involves 2 eyes

monocular depth cues

involves one eye, relative size, texture, interposition, light and shadow

binocular disparity

each eye sees slightly different images; brain can judge depth

convergence

eyes rotate inward to see near objects

shape constancy

perceived shape is constant, even though shape of the image (on retina) varies

color constancy

perceive stimuli as consistent color across varied conditions

figure-ground separation

figures are integrated units of perception

gestalt principles

rules that govern how we perceive objects as wholes within their overall context

common fate

objects moving at the same direction and at the same speed are perceived as a group

synchrony

stimuli that are perceived to occur at the same time are perceived as part of the same event

Non-associative learning

A form of learning that involves responding to a single stimulus; Habituation, sensitization

Associative learning

Occurs when an organism makes connections between 2 or more stimuli/events that occur together in the environment; Classical conditioning, operant conditioning

Learning

Change in an organism’s behavior or thoughts as a result of experience

Habituation

process of responding less strongly over time to repeated stimuli; getting used to a stimulus (adaptation of sensory receptors)

Sensitization

process of responding more strongly over time to repeated stimuli

Classical conditioning

when two stimuli are repeated paired

unconditioned stimulus (US)

produces a reflexive automatic response

unconditioned response (UR)

that automatic response (already there, not learned)

conditioned stimulus (CS)

initially neutral, becomes associated with UCS

Conditioned response (CR)

automatic response now triggered by CS

Acquisition

learning phase; when UCS is paired with CS, after which CS produces (or acquires) CR

extinction

CS appears alone and the CR weakens → Cr eventually eliminated

Spontaneous recovery

extinct CR suddenly emerges again after a delay; relearning happens more rapidly than initial learning

Renewal effect

response extinguished in a new context, but returns in original setting

Generalization

respond to stimuli that are similar to the conditioned stimulus (ex. dog salivating to other bell tones)

discrimination

respond to a particular stimulus but not similar stumili (prevents overgeneralization, ex: dog doesn’t salivate to sound of gong)

blocking

a prior association with a conditioned stimulus prevents learning of an association with another stimulus

preparedness

biological predisposition to learn some associations more quickly than other associations

Taste aversion conditioning

associating nausea with food

fear conditioning

negative associations can be so powerful that they are learned extremely rapidly

chronic drug use

when a drug is used, it is associated with the cues present at the same time

factors that influence classical conditioning

the intensity of the conditioned stimulus

the temporal relationship between the CS and the UCS

how reliably the CS predicts the UCS

the number of pairings of the CS and the UCS

Thorndike’s law of effect

behavior is a function of its consequences

basic assumption

learning is controlled by the consequences of the organism’s behavior

discriminative stimulus

any stimulus that signals the presence of reinforcement

reinforcement

increased likelihood of a behavior being repeated (behavior strengthened)

punishment

decreased likelihood of a behavior being repeated (behavior is weakened)

positive reinforcement

ex: children are given stickers for working hard (adding something good)

negative reinforcement

leaving the house early to avoid the traffic jam (subtracting something bad)

positive punishment

ex: getting a speeding ticket (adding something bad)

negative punishment

being grounded for staying out too late (subtracting something good)

classical conditioning

Automatic behaviors, associate UCS + CS, result: CR

Operant conditioning

Voluntary behaviors, associate behavior + consequence, result: more/less behavior

quantitative law of effect

the effects of reinforcing one behavior depend on how much reinforcement is earned for the behavior’s alternatives

continuous reinforcement

behavior is rewarded every time it is performed

partial reinforcement

behavior is rewarded only some of the time

fixed ratio

reinforce after constant # of responses

variable ratio

reinforce after variable # of responses

fixed interval

reinforce after constant amount of time

variable interval

reinforce after variable amount of time

problems with punishment

doesnt teach the targeted behavior

can create anxiety and subversive behavior

can model bad aggressive behavior

social learning theory

learning is a cognitive process derived from social observation, and does not necessarily require reinforcement