AP Psych--Chapter 5

106969159	psychophysics	the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them
106969160	Gustav Fechner	historic psychologist; first student of psychophysics
106969161	sensation	the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
106969162	perception	the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
106969163	bottom-up processing	analysis that begins with the sensory receptors and works up to the brain's integration of sensory information
106969164	top-down processing	information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations
106969165	absolute threshold	the minimum stimulation needed to detect a particular stimulus 50 percent of the time
106969166	signal detection theory	a theory predicting how and when we detect the presence of a faint stimulus ("signal") amid background stimulation ("noise"). Assumes there is no single absolute threshold and detection depends partly on a person's experience, expectations, motivation, and level of fatigue
106969167	hit	signal present, signal detected
106969168	miss (false negative)	signal present, signal not detected
106969169	false positive	signal not present, signal detected
106969170	correct rejection	signal not present, signal not detected
106969171	subliminal	below one's absolute threshold for conscious awareness
106969172	priming	the activation, often unconsciously, of particular associations in memory
106969173	difference threshold (JND)	"just noticeable difference"-the minimum difference between two stimuli required for detection 50 percent of the time
106969174	Weber's law	principle that, to be percieved as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)
106969175	sensory adaptation	diminished sensitivity as a consequence of constant stimulation
106969176	transduction	conversion of one form of energy into another; in sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret.
106969177	wavelength	the distance from the peak of one light or sound wave to the peak of the next
106969178	hue	the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth
106969179	intensity	the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave's amplitude
106969180	pupil	the adjustable opening in the center of the eye through which light enters
106969181	cornea	the clear tissue that covers the front of the eye
106969182	iris	a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
106969183	lens	the transparent structure behind the pupil that changes shape to help focus images on the retina
106969184	accommodation	the process by which the eye's lens changes shape to focus near or far objects on the retina
106969185	retina	the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
106969186	acuity	sharpness of vision
106969187	nearsightedness	a condition in which nearby objects are seen more clearly than distant objects because distant objects focus in front of the retina
106969188	farsightedness	a condition in which faraway objects are seen more clearly than near objects because the image of near objects is focused behind the retina
106969189	photoreceptors	rods and cones
106969190	rods	retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond
106969191	cones	retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.
106969192	bipolar cells	eye neurons that receive information from the retinal cells and distribute information to the ganglion cells
106969193	ganglion cells	the specialized cells which lie behind the bipolar cells whose axons form the optic nerve which takes the information to the brain
106969194	optic nerve	the nerve that carries neural impulses from the eye to the brain
106969195	optic chiasm	the crossing of the optic nerves from the two eyes at the base of the brain
106969196	lateral geniculate nucleus	the neural cluster on either side of the outside of the thalamus that receives visual input from the optic nerves
106969197	blind spot	the point at which the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there
106969198	fovea	the central focal point in the retina, around which the eye's cones cluster
106969199	feature detectors	nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
106969200	David Hubel and Torsten Wiesel	psychologists; sensation and perception--discovered feature detectors, groups of neurons in the visual cortex that respond to different types of visual stimuli
106969201	parallel processing	the processing of several aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision. Contrasts with the step-by-step (serial) processing of most computers and of conscious problem solving
106969202	Young-Helmholtz trichromatic theory	the theory that the retina contains three different color receptors--one for red, one for green, and one for blue--which, when stimulated in combination, can produce the perception of any color
106969203	opponent-process theory	the theory that opposing retinal processes (red/green, yellow/blue, white/black) enable color vision; for example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
106969204	audition	the sense or act of hearing
106969205	frequency	the number of occurrences within a given time period (usually 1 second)
106969206	decibels	measuring unit for sound energy
106969207	pitch	a tone's experienced highness or lowness; depends on frequency
106969208	middle ear	the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window
106969209	cochlea	a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
106969210	inner ear	the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs
106969211	organ of Corti	organ located in the cochlea; contains receptors (hair cells) that receive vibrations and generate nerve impulses for hearing
106969212	place theory	in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated
106969213	frequency theory	in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch
106969214	sound localization	the way that we locate which direction a sound is coming from
106969215	dichotic listening	in a laboratory situation; headphones on, each ear receives completely different messages
106969216	conduction hearing loss	hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
106969217	sensorineural hearing loss	hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness
106969218	cochlear implant	a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
106969219	gate control theory	theory that spinal cord contains neurological gate that blocks pains signals or allows them to pass. gate is opened by activity of pain going up small nerve fibers & gate is closed by act of large fibers or by info coming from brain
106969220	cutaneous receptors	touch receptors on the skin
106969221	sensory interaction	the principle that one sense may influence another, as when the smell of food influences its taste
106969222	olfaction	the sense of smell
106969223	gustation	the sense of taste
106969224	umami	the taste sensation produced by glutamate; identifies the presence of amino acids in foods (meaty taste)
106969225	papillae	sprouts on the tongue that contain taste buds
106969226	kinesthesis	the system for sensing the position and movement of individual body parts
106969227	vestibular sense	the sense of body movement and position, including the sense of balance
106969228	synesthesia	a condition in which one type of sensory stimulus evokes a secondary and associated response. Example: hearing a sound and that invokes a color
106969878	color constancy	perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object