sensation/perception, sleeping & dreaming, learning

ch 3, ch 11, ch4, ch5 psych

sensation

the process of receiving stimulus energies

perception

the process of organizing and interpreting sensory information so that it makes sense

bottom-up processing

sensory receptors register information about the external environment and send it up to the brain for interpretation 

top-down processing

launched by cognitive processing at the brain’s higher levels, that allows the organism to sense what is happening and to apply that framework to information from the world

selective attention

focusing on a specific aspect of experience while ignoring others

inattentional blindness

failure to perceive a fully-visible, yet unexpected object or event because attention is focused on something else

highlights the limits of attention and perception

perceptual sets

a predisposition or readiness to perceive something in a particular way

visual pareidolia

tendency to perceive meaningful images in meaningless visual stimuli (activates fusiform face area)

fovea

the central region of the retina responsible for sharp central vision and visual acuity

retina

multilayered light-sensitive surface in the eye that records electromagnetic energy and converts it to neural impulses for processing in the brain

rods

the receptor cells in the retina that are sensitive to light but not very useful for color vision

cones

the receptor cells in the retina that allow for color perception

sensory receptors

cells that detect stimulus information and transmit it to afferent nerves and the brain

visual agnosia

an inability to recognize familiar objects by sight, usually due to a lesion in one of the visual association areas

prosopagnosia

an inability or difficulty in recognizing familiar faces: it may be congenital or result from injury or disease of the brain

trichromatic theory

theory stating that color perception is produced by three types of cone receptors in the retina that are particularly sensitive to different, but overlapping, ranges of wavelengths

opponent-process theory

theory stating that cells in the visual system respond to complementary pairs of red-green and blue-yellow colors: a given cell might be excited by red and inhibited by green, whereas another cell might be excited by yellow and inhibited by blue

person perception

the processes by which an individual uses social stimuli to form impressions of others

stereotype

a generalization about a group’s characteristics that does not consider any variations from one individual to another

“beautiful-is-good” stereotype

assumed to have a variety of positive characteristics: better adjusted, socially skilled, friendly, likable, extroverted, apt to achieve superior job performance, etc.

self-fulfilling prophecy 

social expectations that cause an individual to act in such a way that the expectations are realized 

attribution theory 

the view that people are motivated to discover the underlying causes of behavior as part of their effort to make sense of the behavior

fundamental attribution error

observers’ overestimation of the importance of internal traits and underestimation of the importance of external situations when they seek explanations of another person’s behavior

self-serving bias

the tendency to take credit for one’s own successes and to deny responsibility for one’s own failures

circadian rhythms

daily behavioral or physiological cycles that involve the sleep/wake cycle, body temperature, blood pressure, and blood sugar level

suprachiasmatic nucleus

located in the hypothalamus, receives input from the retina, & regulates the pineal gland in the brain that releases the hormone melatonin (makes us sleepy)

pineal gland

a small endocrine gland in the brain that produces melatonin, regulating sleep-wake cycles

melatonin

the hormone that regulates the sleep-wake cycle (circadian rhythm), produced by the pineal gland in response to darkness

theories on the need for sleep 

-animals need to protect themselves at night

-way to conserve energy (metabolism decreases by 5-10%)

-restorative (helps rebuild & replenish wear-and-tear in the brain & body)— enhances immune system ; DNA is repaired, flush out waste-products

-plays a role in brain plasticity—vital to the consolidation of memory

case study - peter tripp

-stayed awake 200 hours, 8 days/nights

-cognitive dysfunction, personality changes, hallucinations

beta waves - stage w (wake)

-concentration & alertness

-observed when person engaged in cognitive tasks, problem-solving, decision-making, or focused mental activites

alpha waves - stage w (wake but drowsy)

most prominent when in a relaxed & calm state, such as during daydreaming/meditation or just before falling asleep

stage N1 (non-REM)

-theta waves, slower frequency

-may experience sudden muscle movements called myoclonic jerks

-light sleep lasting up to 10 min

stage N2 (non-REM)

-sleep spindles: associated with memory consolidation & brain plasticity

-k complexes: involved in maintaining the stability & continuity of sleep

muscle activity decreases, & person is no longer consciously aware of the environment

stage N3 (non-REM)

-delta waves, most difficult to wake sleepers

-sleepwalking, bedwetting (children), sleep talking, sleep terrors occur

-when awakened, ppl are usually confused & disoriented

REM (stage R)

-sleepers drift up through the sleep stages toward wakeful

-EEG pattern for REM sleep shows fast waves similar to those of wakefulness

reports of dreaming by individuals awakened from REM sleep are typically longer, more vivid, more physically active, more emotionally charged, & less related to waking life than reports by those awakened from non-REM sleep

sleep & the brain (neurochemistry)

-REM sleep is initiated by a rise in acetylcholine, which activates the cerebral cortex while the rest of the brain remains relatively inactive

-REM sleep ends when there is a rise in serotonin and norepinephrine, which increases the level of forebrain activity nearly to the awakened state

REM rebound effect

REM sleep plays a crucial role in various cognitive & emotional processes, such as memory consolidation, learning, & emotional regulation—the brain recognizes the need to “catch-up” on this vital stage of sleep to maintain proper functioning

why we dream?

to fulfill wishes, to remember, forget, rehearse, heal, solve problems, keep our brain working

manifest content (freud)

the surface content of a dream, containing dream symbols that disguise the dream’s true meaning

latent content

a dream’s hidden content: the unconscious and true meaning

cognitive theories of dreaming

theory proposing that one can understand dreaming by applying the same cognitive concepts used in studying the waking mind (dreams are essentially subconscious cognitive processing)

activation-synthesis theory

theory that dreaming occurs when the cerebral cortex synthesizes neural signals generated from activity in the lower part of the brain and that dreams result from the brain’s attempts to find logic in random brain activity that occurs during sleep

learning

systematic, relatively permanent change in behavior that occurs through experience

behaviorism

theory of learning that focuses solely on observable behaviors, discounting the importance of mental activity (e.g., thinking, wishing, hoping, etc.)

associative learning

organism makes a connection between two events

classical conditioning

learning process in which a neutral stimulus becomes associated with an innately meaningful stimulus & acquires the capacity to elicit a similar response

-described by pavlov (1903)

pavlov’s studies

before conditioning:

-US (food) —> UR (dog salivation)  NS (bell) —> no response (no salivation)

conditioning:

-NS (bell) + US (food) —> UR (dog salivates)

after conditioning:

-CS (bell) —> CR (dog salivates)

unconditioned stimulus

a stimulus that produces a response without prior learning

unconditioned response

an unlearned reaction that is automatically elicited by the unconditioned stimulus

conditioned stimulus

a previously neutral stimulus that eventually elicits a conditioned response after being paired with the unconditioned stimulus

conditioned response

the learned response to the conditioned stimulus that occurs after a conditioned stimulus—unconditioned stimulus pairing

john b. watson & fear conditioning

before conditioning:

US = loud noise

UR = startle response/crying/fear

NS = white rat

during conditioning:

NS (white rat) + US (loud sound) → UR (startle/crying/fear)

after conditioning:

CS (white rat) → CR (startle/crying/fear)

acquisition

the initial learning of the connection between the unconditioned stimulus and the conditioned stimulus when these two stimuli are paired

generalization

the tendency of a new stimulus that is similar to the original conditioned stimulus to elicit a response that is similar to the conditioned response 

discrimination

the process of learning to respond to certain stimuli and not others

extinction

the weakening of the conditioned response when the unconditioned stimulus is absent

spontaneous recovery

the process in classical conditioning by which a conditioned response can recur after a time delay, without further conditioning 

counterconditioning

a classical conditioning procedure for changing the relationship between a conditioned stimulus and its conditioned response

aversive conditioning

a form of treatment that consists of repeated pairings of a stimulus with a very unpleasant stimulus

habituation

decreased responsiveness to a stimulus after repeated presentations

biological preparedness

the species-specific biological predisposition to learn certain associations faster than others

operant conditioning

a form of associative learning in which the consequence of a behavior changes the probability of the behaviors occurrence (B.F. Skinner)

thorndike’s law of effect

thorndike’s law stating that behaviors followed by positive outcomes are strengthened and that behaviors followed by negative outcomes are weakened

shaping

rewarding successive approximations of a desired behavior

positive reinforcement

the presentation of a stimulus following a given behavior that increases the frequency of that behavior

negative reinforcement

the removal of a stimulus following a given behavior in order to increase the frequency of that behavior

avoidance learning

an organism’s learning that it can altogether avoid a negative stimulus by making a particular response

learned helplessness

through experience with unavoidable aversive stimuli, an organism learns that it has no control over negative outcomes

primary reinforcer

a reinforcer that is innately satisfying: one that does not take any learning on the organism’s part to make it pleasurable

secondary reinforcer

a reinforcer that acquires its positive value through an organism’s experience: a secondary reinforcer is a learned or conditioned reinforcer

schedules of reinforcement

specific patterns that determine when a behavior will be reinforced

positive punishment 

the presentation of a stimulus following a given behavior in order to decrease the frequency of that behavior

negative punishment

the removal of a stimulus following a given behavior in order to decrease the frequency of that behavior

applied behavioral analysis

the use of operant conditioning principles to change human behavior

observational learning

-albert bandura

complex behaviors are the result of exposure to competent models

we imitate or model the behavior of others

bandura showed that people can learn by watching others, without being directly reinforced or punished

-ex: procedure- children observed model, then were placed in a room with toys including a bobo doll to see how they acted

-children exposed to aggressive models were more likely to imitate aggressive behaviors

cognitive factors in learning

-E.C. Tolman (1932) & latent learning

-unreinforced learning not immediately reflected in behavior

-challenge to radical behaviorism, implied reinforcement isn’t necessary

-much more is going on inside a learning organism than mere stimulus-response transactions (i.e. complex cognitive activity occurs)

latent learning/implicit learning

unreinforced learning that is not immediately reflected in behavior

insight learning

a form of problem solving in which the organism develops a sudden insight into or understanding of a problem’s solution