the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
process of organizing and interpreting sensory info, enabling us to recognize meaningful objects and events
analysis that begins with the sensory receptors and works up to the brain's integration of sensory info.
info. processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations
the focusing of conscious awareness on a particular stimulus
failing to see visible objects when our attention is directed elsewhere
failing to notice changes in the environment
study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
min. stimulation needed to detect a particular stimulus 50 percent 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). Assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness.
below one's absolute treshold for conscious awareness
the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (jnd). (p. 122)
the principle that, to be perceived as different, two stimuli must differ by a constant percentage (rather than a constant amount)
diminished sensitivity as a consequence of constant stimulation
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.
the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission
he dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth
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
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.
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.
sensioromotor hearing loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; also called nerve deafness.
the system for sensing the position and movement of individual body parts.
gate control theory
the theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain. The “gate” is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.
the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave’s amplitude.
the adjustable opening in the center of the eye through which light enters
a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
the transparent structure behind the pupil that changes shape to help focus images on the 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 info.
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond
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.
the nerve that carries neural impulses from the eye to the brain
the point at which the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there
the central focal point in the retina, around which the eye's cones cluster
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
the processing of many aspects of a problem simultaneously; the brain's natural mode of info. processing for many functions, including vision. contrasts with the step-by-step (serial) processin gof most computers and of conscious problem solving
3 receptors in the retina that are responsible for the perception of color
opponent process theory
theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. i.e. some cells are stimulated by green and inhibited by red; othrs are stimulated by red and others are inhibited by green
the sense or act of hearing
the number of complete wavelengths that pass a point in a given time (i.e. per second)
a tone's experienced highness or lowness; depends on frequency
a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger neural impulses
in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
a deevice for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
sense of body movement and position, including the sense of balance
principle that one sense may influence another, as whn the smell of food influnces its taste