psych

define - sensation

light hits your retina and then relayed to your brain; receiving stimulus energies from environment and transforming them into neural energy

Whats an example of sensation?

pain from burning your hand

define - perception

brain interprets the information to decide what it is seeing; the way sensory information is organized, intercepted, and consciously experienced

What is an example of perception?

smelling cinnamon rolls but the perception may be thinking of bread your grandma used to bake

define sensory adaptation

continuous and uncharged stimuli we gradually adapt to; focus on changes tend to be the most adaptive response

What is an example of sensory adaptations?

Eyes adjust when its dark so you can see.

What is Bottom-Up Processing?

initiated by sensory input, outside world's influence on perception

What is Top-Down Processing?

initiating by cognitive processing; internal/mental world's influence on perception (ex: once you burn your hand you know not to touch the hot stove)

Define sensory receptors.

specialized cells that selectively detect and transmit sensory information to the brain; cells send signals via distinct neural pathways

What are the 3 types of sensory receptors and what do they do?

1. Photoreception (vision) - detection of light 2. mechanoreception (hear,touch) - detection of pressure, vibration, and movement 3. Chemoreception (smell,taste) - detection of chemical stimuli

What does the Meissners corpuscle, olfactory cells, hair cells, and gustatory cells focus on?

touch, smell, hearing, taste

What are the sensory thresholds?

absolute, noise, difference

define absolute threshold.

the minimum amount of stimulus energy an organism can detect 50% of the time

define noise threshold

any stimulus that interferes with the perception of another stimulus

define difference threshold.

how much stimulus difference is necessary for detection

What is the Just Noticeable Difference (JND)? What happens with low and high stimulus levels?

smallest difference detected 50% of the time; increases as stimulus grows, low levels: small changes can be detected high levels: small changes less noticeable

Whats an example of JND?

when it is quiet you can hear someone whisper but when it is loud you can't hear someone talk

How does attention affect perception?

focus on awareness, selective attention - cocktail party and stroop effect

What is the weapon focus effect?

presence of a weapon causes eyewitness to fail to recall details and less likely to identify a witness.

What is the perceptual set.

mental predisposition to perceive one thing and not another

What are the properties of light?

wavelength, amplitude, purity

what is a wavelength?

distance between wave peaks, perceived as hues, some beyond human sensations

What is Purity?

mixture of wavelengths, perceived as saturated

What is amplitude?

height of wave, perceived as brightness

What are photo-receptor cells?

rods and cones

What are rods?

sensitive to even dim light but not color, functions well in low illumination, humans have about 120 million rods

What are cones?

respond to color, operate best under high illumination, humans have about 6 million cones

what is a fovea?

densely populated with cones

What are visual processing?

feature detectors, parallel processing, binding

What are feature detectors? What do they respond to?

specialized cells in the visual cortex, respond to size, shape, color, movement, or a combination

What is parallel processing?

"seeing" all of the characteristics of a stimulus at once

What is binding?

integrating information about a stimulus

What are the 2 theories of color vision?

Trichromatic and Opponent-Process Theory

What are the 3 types of receptors of Trichromatic Theory?

green, blue, and red cones,

What is afterimage in the opponent-process theory?

sensation remains after a stimulus is removed

What is the opponent-process theory?

complementary color pairs (red-green, blue-yellow)

What are the dimensions of visual perception?

shape, depth, motion, constancy

What is the Gestalt Psychology for the shape dimension?

perceptions are naturally organized according to certain patterns, whole is different from the sum

What is the Gestalt principle for the shape dimension?

closure, proximity, similarity

What is the figure-ground relationship?

automatically sort visual information to identify what is foreground (figures) and background (ground)

What is depth?

how we judge how far things are away if the images on our retina is two dimensional, present at birth

What are bionocular cues?

depth cues using both eyes; disparity and convergence

What are monocular cues?

depth cues requiring one eye; size, height, linear perception, overlap, shading, texture gradient

What is constancy?

recognition that objects don't physically change despite changes in vantage point and viewing conditions

What happens with sensory info with constancy?

sensory info (retinal image) changes, but perceptual interpretation doesn't

What happens when you listen to loud noise for a long time?

overwork hair cells in the ear, cause cells to die

What happens to cells when there are loud noises?

damage cells and membrane in cochlea

What are the 2 theories of hearing with pitch perception?

Place Theory - location of stimulation, only explains perception of high frequencies Frequency theory - frequency of nerve firing, volley principle

What is consciousness?

awareness and arousal

What is awareness?

external events and internal sensations which occurs under conditions of arousal

What is arousal?

physiological state of being engaged with the environment

What part of the reticular activating system determines wakefulness?

brain stem, medulla, thalamus

what is the theory of the mind?

understanding that other people think and have private experiences

What are the levels of awareness?

higher-level consciousness, lower-level consciousness, subconscious awareness, no awareness

What is the higher-level consciousness?

controlled processing - requires selective attention, involves prefrontal cortex executive function - planning, problem solving, actively focusing efforts toward a goal

What is the lower-level consciousness?

automatic processes- require little attention/conscious effort, do not interfere with other activities; daydreaming - between active consciousness and dreaming while asleep, wandering thoughts

What is subconscious awareness?

waking - incubation; sleep/dreams - low levels of consciousness of outside world

What alters states of consciousness?

drug states, fatigue, illness, trauma, mediation, hypnosis, mental disorders

define circadian rhythms.

24-hour cycles, monitored by suprachiasmatic nucleus (SCN)

what is melatonin?

hormone released by the pineal gland in order to promote sleep, doesn't make up go to sleep

What happens with bright morning light?

activities light-sensitive proteins that trigger SCN to decreased production of melatonin in morning and increased production in evening

How can lights reduce the amount of melatonin?

bright lights in the evening

What can consuming melatonin help?

jet lagging or insomnia

define sleep debt

difference between the amount of sleep someone needs and actually gets

What does sleep deprivation result in?

decreased activity in thalamus and prefrontal cortex, inability to sustain attention, poor decision making and problem solving

What does an EEG measure?

electrical activity in the brain

What are the 2 stages of wakefullness?

beta waves (W-alert) - high frequency, low amplitude, desynchronous alpha waves (W-relaxed) - lower frequency, increase amplitude, more synchronous

What is the first stage of sleep?

Stage N1 (non-REM1) - theta waves, slower frequency, low amplitude (but greater than alpha), myoclonic jerks

What is the second stage of sleep?

Stage N2 (non-REM2) - continued theta waves, sleep spindles: sudden increase in wave frequency, still light sleep

What is the third stage of sleep?

Stage N3 (non-REM3) - delta waves, slowest frequency and highest amplitude, deep sleep, bed wetting, sleep walking/talking

What is Stage R of sleep?

REM Sleep - Rapid Eye Movement, EEG similar to relaxed wakefulness, dreaming

What is the typical time for sleep cycles?

90-100 minutes per cycle, several cycles a night, REM stages get longer during the night

percent of a typical night of the stages?

60% - stage N1 and N2 20% - stage N3 20% - REM

define reticular formation

critical role in sleep and arousal

how does neurotransmitters affect REM sleep?

rise in acetylcholine and sleep ends with rise in serotonin and norepinephrine

define dreams.

sequence of images, emotions and thoughts passing through a sleeping person's mind

what activities do dreams increase?

visual, motor, emotional and autobiographical memory regions of the brain

what activities do dreams decrease?

activity in frontal lobes which control rational thought and logical decision making

What is the neural static theory?

our brain is trying to interpret random neurons firing

What is improved memory theory?

dreams help us consolidate each day's memories

What is brain stimulation theory?

dreams help develop and preserve neural pathways

What is the evolution theory?

our brain is trying to prepare use for worst-case scenarios

What is the overnight therapy theory?

dreams help us remove negative emotions from distressing memories

Why can't we remember dreams?

norepinephrine and the brain regions associated with memory are barely active during REM sleep; We cannot access that information once we are awake. Researchers believe people forget dreams due to changing levels of acetylcholine and norepinephrine during sleep.

How do psychoactive drugs act on the nervous system?

alter consciousness, modify perceptions, change moods

How do reward pathway for psychoactive drugs move?

Ventral tegmental area (VTA) --\> nucleus accumbens (NAC) --\> prefrontal cortex, increasing dopamine transmission

What does alcohol do to areas of the brain?

increases GABA, blocks REM

Examples of depressants

alcohol, barbiturates, tranquilizers, opioids

Define depressants

decrease mental and physical activity

examples of stimulants

caffeine, amphetamines, cocaine, MDMA (ecstasy)

what are stimulants

increase CNS activity

examples of hallucinogens

Marijuana, LSD, MDMA (ecstasy)

What are Halucinogens?

modify perceptual experiences

barbiturates

nembutal/seconal

tranquilizers

valium/xanax

opioids

narcotics, lead to euphoria and increase appetite

caffeine

most used psychoactive drug, 1/2 life of 5 years

Ecstasy

"Empathogen" - users tend to feel warm bonds with others; releases serotonin, dopamine, and norepinephrine

What are the 4 steps in hypnosis?

1. Distractions are minimized 2. told to concentrate on something specific 3. told what to expect (relaxation, floating sensation) 4. certain obvious events/feelings are suggested

define hypnosis

altered attention and expectation, unusually receptiveness to suggestions