Unit 1.6 - Sensation - AP Psychology

sensation

the process by which our sensory receptors and nervous system receive and represent stimulus energies from environment

perception

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events

bottom-up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information (sensation first)

top-down processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations (experience first)

transduction

conversion of one form of energy into another

How do senses transfer to transduction?

by receiving sensory stimulation, transforming stimulation into neural impulses, delivering neural impulses to the brain

psychophysics

the study of relationships between the physical characteristics of stimuli, and our psychological experience of them

threshold

the level of stimulation required to trigger a neural impulse

absolute threshold

the lowest intensity at which a stimulus can be detected, typically defined as the point where a person can detect it 50% of the time

subliminal perception

Stimuli that are too weak or too brief to be consciously seen or heard

priming

An enhanced ability to think of a stimulus, such as a word or object, as a result of a recent exposure to the stimulus by experiences

difference thresholds

the smallest detectable difference between two stimuli, meaning how much a stimulus needs to change for someone to notice a difference

Weber's Law

to be perceived as different, two stimuli must differ by a constant minimum percentage

Sensory Adaptation

diminished sensitivity as a consequence of constant stimulation

Light Energy

Energy produced by the vibrations of electrically charged particles

puity of light waves determine...

vividness or clearness

height of a light waves determines...

intensity or brightness

rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision

cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions

blindspot

the point at which the optic nerve leaves the eye, no receptor cells are located there

fovea

the central focal point in the retina, around which the eye's cones cluster

ganglion cells

final output neurons of the retina which collects the electrical messages concerning visual signals from two layers of nerve cells

bipolar cells

transports information from rods and cones to ganglion cells

Young-Helmholtz trichromatic theory

theory of color vision based on additive color mixing; suggest that the retina contains three types of color receptors, cones: red, green, blue

opponent-process theory

the theory that opposing retinal processes enable color vision

feature detectors

nerve cells in the brain's visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement

prosopagnosia

inability to recognize faces

parallel processing

the processing of many aspects of a problem simultaneously

audition

the sense or act of hearing

sound waves

a longitudinal wave consisting of compressions and rarefactions, which travels through a medium

frequency

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

cochlea

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

hammer, anvil, stirrup

Three bones of the middle ear

ear canal

a tube running from the outer ear to the middle ear

oval window

membrane at the enterance to the cochlea through which the ossicles transmit vibrations

ear drum

a tightly stretched membrane at the end of the ear canal that vibrates when hit by sound waves

sensorineural hearing loss

hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

place theory

theory of pitch that states that different pitches are experienced by the stimulation of hair cells in different locations

frequency theory

theory of pitch that states that pitch is related to the speed of vibrations in the basilar membrane

basilar membrane

membrane supporting the organ of Corti and hair cells in the cochlea

organ of corti

Center part of the cochlea, containing hair cells, canals, and membranes

sound localization

how we can locate sounds based on which ear they strike first

just noticeable difference

difference in stimuli required to detect a difference between the stimuli

synesthesia

describing one kind of sensation in terms of another

retina

Light sensitive layer of the eye; contains rods and cones

visual nerve

carries neural impulses from the eye to the brain

accommodation

the process by which the eye's lens changes shape to focus near or far objects on the retina

photoreceptors

respond to light

afterimages

Sensations that linger after the stimulus is removed

dichromatism

one cone type is missing or malfunctioning

olfactory system

the sensory system for smell

Touch, sense of touch

tactile sense, vital for development and survival; sensations include pain, pressure, touch temperature; processed by parietal lobe

What is the Gate-control Theory?

A theory stating that the spinal cord has a 'gate' that can either block or allow pain signals to reach the brain.

How is the 'gate' in the Gate-control Theory opened and closed?

It is opened by pain signals traveling up small nerve fibers and closed by activity in larger fibers or by information from the brain.

Nociceptors

sensory receptors that enable the perception of pain in response to potentially harmful stimuli

phantom limb sensation

patients who have had a limb amputated may still experience sensations such as itching, pressure, tingling, or pain as if the limb were still there

smell sense (olfaction)

only sense that bypasses the thalamus; works closly with taste through sensory interaction

how do you smell?

odorants enter nasal cavity, stimulates receptors, bypasses the thalamus and goes straight through the temporal lobe to be processed; also why smell is closely connected to memory

Sense of Taste (Gustation)

receptor organs are taste buds containing gustatory receptors (on tongue)

umani

the taste of savory foods

oleogustus

the taste of fat

papillae

taste buds

sensory interaction

the principle that one sense may influence another

vestibular sense

the sense of body movement and position, including the sense of balance

kinesthetic sense

sense of the location of body parts in relation to the ground and each other

phrenology

lead to focusing on localization

farsighted

a condition in which faraway objects are seen more clearly than near objects

nearsighted

a condition in which nearby objects are seen more clearly than distant objects

volley principle

The theory holding that groups of auditory nerve fibers fire neural impulses in rapid succession, creating volleys of impulses.

pinna

the visible part of the ear

auditory canal

short tunnel that runs from the pinna to the eardrum

eardrum

a thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate

ossicles

three tiny bones in the middle ear

iris

Colored part of the eye

pupil

allows light to enter the eye

cornea

the transparent layer forming the front of the eye.

blind spot

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

optic nerve

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

vision receptors

rods and cones in the retina

vision key brain areas

occipital lobes

hearing receptors

cochlear hair cells in the inner ear

hearing key brain areas

temporal lobes

touch receptors

respond to mechanical stimulation of the skin

touch key brain areas

somatosensory cortex (parietal lobe)

taste receptors

chemical receptors on the tongue that decode molecules of food or drink to identify them

taste key brain areas

frontal temporal lobe border

smell receptors

millions of olfactory cells (modified neurons) in the roof of the nasal cavity

smell key brain areas

olfactory bulb and temporal lobe

kinesthesia receptors

nerve endings in muscles, tendons, and joints

kinesthesia key brain areas

cerebellum and parietal lobe

vestibular sense receptors

hairlike receptors in the semicircular canals and vestibular sacs

vestibular sense key brain areas

cerebellum