sensation and perception - terms and definitions Flashcards
absolute threshold
the minimum amount of stimulation that an organism can detect.
additive colour mixing
works by superimposing lights, putting more light in the mixture than exists in any one light by itself
afterimage
a visual image that persists after a stimulus is removed
auditory localization
locating the source of a sound in space.
basilar membrane
which runs the length of the spiralled cochlea, holds the auditory receptors.
binocular depth cues
are clues about distance based on the differing views of the two eyes.
bottom-up processing
a progression from individual elements to the whole
cochlea
a fluid-filled, coiled tunnel that contains the receptors for hearing.
colour-blindess
encompasses a variety of deficiencies in the ability to distinguish among colours.
complementary colours
are pairs of colours that produce grey tones when mixed together.
cones
are specialized visual receptors that play a key role in daylight vision and colour vision.
depth perception
involves interpretation of visual cues that indicate how near or far away objects are.
distal stimuli
are stimuli that lie in the distance (i.e., in the world outside the body).
door-in-the-face technique
technique involves making a large request that is likely to be turned down as a way to increase the chance that people will agree to a smaller request later
feature analysis
is the process of detecting specific elements in visual input and assembling them into a more complex form.
feature detector
neurons that respond selectively to very specific features of more complex stimuli.
fovea
is a tiny spot in the centre of the retina that contains only cones; visual acuity is greatest at this spot.
frequency theory
holds that perception of pitch corresponds to the rate, or frequency, at which the entire basilar membrane vibrates.
gate-control theory
holds that incoming pain sensations must pass through a “gate” in the spinal cord that can be closed, thus blocking ascending pain signals.
gustatory system
the sensory system for taste
just noticeable difference (JND)
is the smallest difference in the amount of stimulation that a specific sense can detect.
kinesthetic system
monitors the positions of the various parts of the body.
lens
is the transparent eye structure that focuses the light rays falling on the retina.
monocular depth cues
are clues about distance based on the image in either eye alone.
olfactory system
the sensory system for smell
opponent process
colour perception depends on receptors that make antagonistic responses to three pairs of colours.
optic chiasm
the point at which the optic nerves from the inside half of each eye cross over and then project to the opposite half of the brain.
optic disk
a place in the retina where the optic nerve fibres exit the eye
perceptual constancy
is a tendency to experience a stable perception in the face of continually changing sensory input.
perceptual hypothesis
is an inference about which distal stimuli could be responsible for the proximal stimuli sensed.
perceptual set
a readiness to perceive a stimulus in a particular way.
pheromones
are chemical messages, typically imperceptible, that can be sent by one organism and received by another member of the same species.
phi phenomenon
is the illusion of movement created by presenting visual stimuli in rapid succession.
pictorial depth cues
clues about distance that can be given in a flat picture.
place theory
holds that perception of pitch corresponds to the vibration of different portions, or places, along the basilar membrane.
primary colours
colour can be matched by the additive mixture of three primary colours.
proximal stimuli
the stimulus energies that impinge directly on sensory receptors.
psychophysics
the study of how physical stimuli are translated into psychological experience.
pupil
is the opening in the centre of the iris that helps regulate the amount of light passing into the rear chamber of the eye.
receptive field
of a visual cell is the retinal area that, when stimulated, affects the firing of that cell.
retina
is the neural tissue lining the inside back surface of the eye; it absorbs light, processes images, and sends visual information to the brain.
retinal disparity
which refers to the fact that objects project images to slightly different locations on the right and left retinas, so the right and left eyes see slightly different views of the object.
reversible figure
a drawing that is compatible with two interpretations that can shift back and forth.
rods
are specialized visual receptors that play a key role in night vision and peripheral vision.
saccades
These eye movements are referred to as saccades.
sensation
is the stimulation of sense organs. Perception is the selection, organization, and interpretation of sensory input
signal-detection theory
proposes that the detection of stimuli involves decision processes as well as sensory processes, which are both influenced by a variety of factors besides stimulus intensity
sensory adaption
is a gradual decline in sensitivity due to prolonged stimulation.
subliminal perception
the registration of sensory input without conscious awareness
subtractive colour
works by removing some wavelengths of light, leaving less light than was originally there.
synesthesia
a condition in which perceptual or cognitive activities (e.g., listening to music, reading) trigger exceptional experiences (e.g., of colour, taste)
threshold
point between energy levels that do and do not have a detectable effect.
top-down processing
a progression from the whole to the elements
trichromatic theory
of colour vision holds that the human eye has three types of receptors with differing sensitivities to different light wavelengths.
vestibular system
which responds to gravity and keeps you informed of your body’s location in space.
visual illusion
involves inexplicable discrepancy between the appearance of a visual stimulus and its physical reality.
weber’s law
states that the size of a just noticeable difference is a constant proportion of the size of the initial stimulus.
