Terms : Hide Images
| 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 |
