psychology sensation and perception

sensation

sensation

detection of physical energy from the environment and the encoding of it as neural signals

perception

selecting, organizing, and interpreting of our sensations

bottom-up

not knowing what's coming; pure sensory experience; no prior knowledge

top-down

you have an idea of what's coming; influences your experiences

absolute threshold

the lowest level of stimulation that a person can detect; 50% of the time ex) the sight and hearing test

difference threshold

the smallest change in stimulation that a person can detect; the point you can tell the difference between something

signal detection theory

predicts when we will detect weak signals

weber's law

the concept that a just-noticeable difference in a stimulus is proportional to the magnitude of the original stimulus; a noticeable difference

sensory adaptation

getting used to a sense; ex)smelling something gross and it goes away after a few minutes

habituation

a general accommodation to unchanging environmental conditions; weakening of response to stimulus; ex) recognizing the noise of the ac

transduction

transformation of physical stimuli into neural impulses for our brain to interpret; occurs in the retina

wavelength

color; cones

amplitude

brightness; rods

light pathway through the eye

cornea, iris/pupil, lens, retina(rods and cones)

fovea

high concentration of cones

visual agnosia

inability to recognize or interpret objects in the visual field

color blindness

genetic inability to distinguish differences in hue; can't identify different wavelengths

parallel processing

taking in and processing of various sensory information simultaneously

trichromatic theory

red, blue, and green

color constancy

ability to recognize color of an object despite changes in light

perceptual/shape constancy

ability to recognize a shape despite its angle changing

size constancy

ability to perceive an object as being the same size despite the fact that the size of its retinal image changes depending on its distance from the observer

perceptual set

notice only certain aspects of an object or situation while ignoring other details

noise pathway through the ear

outer ear, middle ear, oval window, inner ear, auditory nerve, thalamus, temporal lobe

volume

amplitude; frequency of wavelengths determines pitch

tinnitus

ringing or sounds in the ear with no external source

sensorineural hearing loss

hearing loss due to failure of the auditory nerve; due to age

conduction hearing loss

problems with the mechanical system that results in the conduction of sound waves; hearing aids can help(amplifies sound)

place theory

we detect different pitches because different sound waves trigger activity at different places along the cochlear basilar membrane

frequency theory

the rate of nerve impulses traveling up to the auditory nerve matches the frequency of the tone, allowing us to determine pitch

taste

gustatory sense

taste buds

modified skin cells; 50 receptor cells per bud

basic taste sensations

sweet, salty, sour, bitter, umami

smell

olfactory sense

olfactory cells

line olfactory epithelium of the nasal passage

scent pathway through the nose

olfactory receptors, olfactory bulb, cerebral cortex, hippocampus, amygdala, hypothalamus

touch

tactile sense

types of sensations

pressure, warmth, cold, pain

phantom sensations

feeling pain in a place that doesn't exist; ex) amputees

substance p

neurotransmitter that relays pain

gate control pain

messages from the brain/body can "close the gate" for pain messages

vestibular system

balance/equilibrium

selective attention

at any moment our awareness focuses on only a limited aspect of all that we experience

visual capture

vision competes with other senses, usually wins

inattentional blindness

inability to see/notice things due to attention being redirected

change blindness

something in our environment changes, but we don't noticeq

monocular cues

cues that can be detected with only one eye

binocular cues

cues that can be detected with two eyes

retinal desparity

our retinas pick up on 2 slightly different images; our brain interprets this as relative distance; BC

convergence

eyes move inward when something is coming toward you; BC

relative height

higher things in our field of vision are perceived as further away; MC

relative size

the smaller the image, the further away it is; MC

relative clarity

the further away something is, the more foggy/hazy it is; MC

interposition

if an object partially blocks our view, we thinks it's closer;MC

linear perspective

parallel lines that appear to converge with distance; MC

texture gradient

objects closer to us are drawn with more detail; MC

convergence

our brain interprets to help us discern objects moving towards us; BC

motion parallax

items that are close, appear to be moving faster in motion that items far away; MC

phi phenomenon

the illusion of motion

gestalt

german for whole or form

gestalt principles

closure, proximity, similarity, continuity

cornea

the clear, dome shaped tissue covering the front of the eye

iris

the colored part of the eye; controls the amount of light that enters the eye by changing the size of the pupil

lens

a crystalline structure located just behind the iris; focuses light onto the retina

optic nerve

the nerve that transmits electrical impulses from the retina to the brain

pupil

the opening in the center of the iris; changes its size as the amount of light changes

retina

sensory tissue that lines the back of the eye; contains millions of rods and cones that convert light rays into electrical impulses that are relayed to the brain via the optic nerve

vitreous

a thick, transparent liquid that fills the center of the eye; mostly water and gives the eye its form and shape

anvil

a tiny bone that passes vibrations from the hammer to the stirrup

cochlea

a spiral shaped, fluid filled inner ear structure; lined with cilia that move when vibrated and cause a nerve impulse to form

eardrum

a thin membrane that vibrates when sound waves reach it

eustachian tube

a tube that connects the middle ear to the back of the nose; it equalizes the pressure between the middle ear and the air outside

hammer

a tiny bone that passes vibrations from the eardrum to the anvil

nerves

carry electro-chemical signals from the inner ear(cochlea) to the brain

outer ear canal

the tube which sound travels through the eardrum

pinna

the visible part of the outer ear; collects sounds and directs it into the outer ear canal

semicircular canals

three loops of fluid filled tubes that are attached to the cochlea in the inner ear; maintain sense of balance

stirrup

tiny, u-shaped bone that passes vibrations frim the stirrup to the cochlea; smallest bone in the human body

ossicles

the three bones in the ear (sah)