64 terms

Chapter 3 Flashcards

an unelaborated elementary awareness of stimulation
receptor cell
a specialized cell that responds to a particular type of energy
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.
absolute threshold
the lowest level of stimulation that a person can detect
(physiology) the responsive adjustment of a sense organ (as the eye) to varying conditions (as of light)
difference threshold
the smallest change in stimulation that a person can detect
Weber's law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)
transparent anterior portion of the outer covering of the eye
contractile aperture in the iris of the eye
muscular diaphragm that controls the size of the pupil
a transparent optical device used to converge or diverge transmitted light and to form images
the light-sensitive membrane covering the back wall of the eyeball
area consisting of a small depression in the retina containing cones and where vision is most acute
the different energies represented in the electromagnetic spectrum
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.
bipolar cells
eye neurons that receive information from the retinal cells and distribute information to the ganglion cells
visual acuity
sharpness of vision
dark adaptation
the process of adjusting the eyes to low levels of illumination
light adaptation
the process of adjusting the eyes to relatively high levels of illumination
an image (usually a negative image) that persists after stimulation has ceased
ganglion cells
the specialized cells which lie behind the bipolar cells whose axons form the optic nerve which takes the information to the brain
optic nerve
the cranial nerve that serves the retina
blind spot
the point where the optic nerve enters the retina
optic chiasm
the crossing of the optic nerves from the two eyes at the base of the brain
feature detectors
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
the act of soaking thoroughly with a liquid
the location of a visual perception along the black-to-white continuum
additive color mixing
Formation of colors by superimposing lights, putting more light in the mixture than exists in any one light by itself.
subtractive color mixing
Formation of colors by removing some wavelengths of light, leaving less light than was originally there.
trichromatic theory
Visual theory, stated by Young and Helmholtz that all colors can be made by mixing the three basic colors: red, green, and blue; a.k.a the Young-Helmholtz theory.
people who have normal color vision
color blindness
genetic inability to distinguish differences in hue
People who are blind to either red-green or yellow-blue
People who cannot perceive any color, usually because their retinas lack cones.
opponent-process theory
the theory that opposing retinal processes enable color vision
the particular auditory effect produced by a given cause
sound waves
vibrations of the air or of another medium
the number of observations in a given statistical category
the unit of frequency
the property of sound that varies with variation in the frequency of vibration
greatness of magnitude
a logarithmic unit of sound intensity
tones that result from sound waves that are multiples of the basic tone; primary determinant of timbre
(music) the distinctive property of a complex sound (a voice or noise or musical sound)
oval window
fenestra that has the base of the stapes attached to it
the snail-shaped tube (in the inner ear coiled around the modiolus) where sound vibrations are converted into nerve impulses by the Organ of Corti
basilar membrane
a membrane in the cochlea that supports the Organ of Corti
organ of Corti
the hearing organ of the inner ear
auditory nerve
a composite sensory nerve supplying the hair cells of the vestibular organ and the hair cells of the cochlea
place theory
in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated
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
volley principle
The theory holding that groups of auditory nerve fibers fire neural impulses in rapid succession, creating volleys of impulses.
olfactory bulb
one of two enlargements at the terminus of the olfactory nerve at the base of the brain just above the nasal cavities
odorless chemicals that serve as social signals to members of one's species
taste buds
sense receptors in the tongue that respond to sweet, salty, sour, bitter, umami, and perhaps fat
kinesthetic senses
senses that provide information about movement, posture, and orientation
stretch receptors
receptors that sense muscle stretch and contraction
Golgi tendon organs
located in the tendon, both at the muscle origin and insertion
vestibular senses
the senses of equilibrium and body position in space
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
biopsychosocial theory
the theory that the interaction of biological, psychological, and cultural factors influence the intensity and duration of pain.
placebo effect
any effect that seems to be a consequence of administering a placebo