Sensations

ap psychology sensations unit :3

sensation

our sensory receptors + nervous system receive and represent stimulus energies from our environment

sensory receptors

sensory nerve endings that respond to stimuli

perception

our brain organizes + interprets sensory information, enabling us to recognize objects + events as meaningful

bottom-up processing

information processing that begins with the sensory receptors + works up to the brain’s integration of sensory information

top-down processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing onto our experience + expectations

transduction

conversion of one form of energy into another in sensation, the transforming of physical energy, such as sight, sounds, + smells, into neural impulses the brain can interpret

psychophysics

the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them

absolute threshold

the minimum stimulus energy needed to detect a particular stimulus 50% of the time

signal detection theory

a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise)

subminimal

below one’s threshold for conscious awareness

difference threshold or JND

the minimum difference between two stimuli required for detection 50% of the time; we experience the difference threshold as just a noticeable difference

weber’s law

to be perceived as different, two stimuli must differ, by a constant minimum percentage (rather than a constant amount)

sensory adaptation

diminished sensitivity as a consequence of constant stimulation (our diminished sensitivity to routine odors, sights, + touches) focuses our attention on informative changes in our environment

short wavelengths (vision)

high frequency (blue-ish colors)

long wavelengths (vision)

low frequency (red-ish colors)

great amplitude (vision)

bright colors

small amplitude (vision)

dull colors

hue

the dimension of color that is determined by the wavelength of light; what we know as the color named blue, green, etc…

intensity

the amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness (determined by amplitude)

cornea

eye’s clear, protective over layer, covering the pupil and iris

pupil

the adjustable opening in the center of the eye through which light enters

iris

a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the sizes of the pupil opening

lens

the transparent structure behind the pupil that changes shape to help focus images on the retina

retina

the light sensitive back inner surface of the eye, containing the receptor rods and cones + layers of the neurons that begin the processing of visual information

accommodation

in sensation and perception, the process by which the eye’s lens changes shape to focus images or near or far objects on the retina/ in developmental psychology, adapting our current schemas (understandings) to incorporate new information

rods

retinal receptors that detect black, white, and gray and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond

optic nerve

the nerve that carries neural impulses from the eye to the brain

blind spot

the point at which the optic nerve leaves the eye creating a “blind” spot because no receptor cells are located there

fovea

the central focal point in the retinol, around which the eye’s cluster

young - helmholtz trichromatic (three-color) theory

the retina contains three different types of color receptors (one most sensitive to red, one to green, one to blue, which, when stimulated in combination, can produce the perception of color)

opponent-process theory

opposing retinol processes (red-green, blue-yellow, white-black), enable color vision

parallel processing

processing multiple aspects of a stimulus or problem simultaneously

feature detectors

specialized nerve cells in visual cortex, respond to specific features of the visual stimulus such as shape, angle movement, + also passes information onto other cortical areas. where supercell clusters respond to more complex patterns

audition

the sense or act of hearing

frequency

the number of complete wavelengths that pass a point in a given time

pitch

a tone’s experienced highness or lowness; depends on frequency

short wavelengths (hearing)

high frequency (high-pitched sounds)

low wavelengths (hearing)

low frequency (low-pitched sounds)

great amplitude

loud sounds

small amplitude

soft sounds

middle ear

the chamber between the eardrum and cochlea containing three tiny bones that concentrate the vibrations of the eardrums on the cochlea’s oval window

cochlea

a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses

inner ear

innermost part of ear; containing the cochlea, semicircular canals + vestibular sacs

sensineural hearing loss (nerve deafness)

most common form of hearing loss, caused by damage to the cochlea’s receptor cells or to the auditory nerve; also called nerve deafness

conduction hearing loss

a less common form of hearing loss, caused by damage to the mechanical system that conducts sound waves to the cochlea

cochlear implant

a device for converting sounds into electrical signals + stimulating the auditory nerve through electrodes threaded into the cochlea

place theory

links the pitch we hear with the place where the cochlea’s membrane is stimulated (also called place coding)

frequency theory

the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch (also called temporal coding)

vision

light waves striking the eye, rods + cones in the retina, occipital lobes

hearing

soundwaves striking the outer ear, cochlear hair cells (cilia) in the inner ear, temporal lobes

touch

pressure, warmth, cold, harmful chemicals, receptors (including pain-sensitive nociceptors), mostly in the skin, which detect pressure, warmth, cold, and pain, somatosensory cortex

taste

chemical molecules in the mouth, basic taste receptors for sweet, sour, salty, bitter, umami, and oleogustus, frontal/temporal lobe border

smell

chemical molecules breathed in through the nose, millions of receptors at the top of the nasal cavities, olfactory bulb

kinesthesis (position + movement)

any change in position of a body part, interacting with vision, kinesthetic sensors in the joints, tendons + muscles (proprioceptors), cerebellum

vestibular sense (balance + movement)

movement of fluids in the inner ear caused by head/body movement, hair-like receptors (cilia) in the ear’s semicircular canals and vestibular sacs, cerebellum

gate-control theory

the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass in the brain, the “gate” controls the transmission of pain messages to the brain

gustation

our sense of taste

basic tastes

sweet - energy source

salty - sodium essential to physiological processes

sour - potentially toxic acid

bitter - potential poisons

umami - proteins to grow and repair tissue

oleogustus - fats for energy, insulation, and cell growth

sensory interaction

one sense may influence another, as when the smell of food influences its taste

embodied interaction

the influence of bodily sensations, gestures, and other states on cognitive preferences + judgements