the least amount of energy that can be detected as a stimulation 50 percent of the time
The smallest change in stimulation that can be detected 50 percent of the time.
The principle that the just noticeable difference for any given sense is a constant proportion of the stimulation being judged
receptor cells in the retina repsonsible for night vision and perception of brightness- 20 million.
neurons that have only one axon and one dendrite; in the eye, these neurons connect the receptors on the retina to the ganglion cells.
the bundle of acons of ganglion cells that carries neural messages from each eye to the brain
place on the retina where the axons of the ganglion cells leave the ye and where there are no receptors
point near the base of the brain where soem fibers in the optic nerve from each eye cross to teh other side of the brain
subtractive color mixing
the process of mixing pigments, each of which absorbs some wavelenghts of light and reflects others
theory of color vision that all color perception derives from three different color receptors in the retina (usually red, green, and blue receptors).
theory of color vision that three sets of color receptors (yellow-blue, red-green, black-white) respond in either/ or fashion to determine the color you expereience
a psychological experience created by the brain in response to changes in aire pressure that are received by the auditory system.
changes in pressure caused when molecules of air or fluid collide with one another and then move apart again
auditory experienec corresponding primarily to frequency of sound vibrations, resulting in a higher or lower tone.
tones that result from sound waves that are multiples of the basic tone; primary determinant of timbre
ammer, avil, stirrup
the three small bones in the middle ear that relay vibrations of the eardrum to the inner ear.
membrane across the opening between the middle ear and inner ear that conducts vibrations to the cochlea
Part of the inner ear containing fluid that vibrates which in turn causes the basilar membran to vibrate.
vibrating membrane in the cochlea of the inner ear; it contains sense receptors for sound
organ of corti
structure on the surface of the basilar membrane that contains the receptors cells for hearing
theory that pitch is determined by the location of greatest vibrations of the basilar membrane
theory that pitch is determined by the frequency with which hair cells in the cochlea fire
Refinement of frequency theory; receptors in ear fire in sequence, one group thenanother, etc., complete patter of firing corresponds to the frequence of sound.
peromone vomeronasal organ (VNO)
Location of receptors for pheromones in teh roof of the basal cavity
sacs in the inner ear that are responsible for sensing gravitation and forward, backward, and vertical movement.
gate control theory
theory that a "neurological gate" in the spinal cord controls the transmission of pain messages to the brain.
Pain relief occurs when a person believes a pill or procedure will reduce pain; caused by endorphins
specialized brain cells that only repsond to particular elements of the visual field such as movement or lines of specific orientation.
tendency to perceive objects as stable and unchanging despite changes in sensory stimulation.
Perception of an object as the same size regardless of the distance from which it is viewed
perception of brightness as the same. even though the amount of light reaching the retina changes.
inclination to perceive familiar objects as retaining their color despite changes in sensory information.
monocular distance cue in which one object, partyle blocking a second object, is perceived as being closer
monocular cue to distance and depth based on the fact that two parallel lines seem to come together at the horizon
moncular cue to distance and depth based on the fact that more distant objects are likely to appear hazy and blurred.
moncular cue to distance and depth based on the fact that the higher on the horizonal plane an objects is, the farther away it appears.
monocular cue to distance and depth based on the fact that objects seem at greater distances appear to be smoother and less textured
monocular cue to distance and depth based on the fact that shadows often appear on the parts of objects that are more distant
monocular distance cue: objects closer than point of visual focus seem to move oppostie viewer's moving head, and objects beyond that focus point seem to move same direction.
combination of two retinal images to give three-dimensional perceptual experience.
binocular distance cue based on the differnece between the images cast on the two retinas when both eues are focused on teh saem object.