sensory Flashcards
cornea
the clear hard covering that protects the lens of the eye.
pupil
the opening in the iris through which light enters the eye.
iris
the muscle that forms the colored part of the eye; it adjusts the pupil to regulate the amount of light that enters the eye.
lens
the structure that sits behind the pupil; it bends the light rays that enter the eye to focus images on the retina.
accommodation
the process by which the muscles control the shape of the lens to adjust to viewing objects at different distances.
retina
the thin layer of nerve tissue that lines the back of the eye.
photoreceptors
cells in the retina (called rods and cones) that convert light energy into nerve energy.
rods
photoreceptors that function in low illumination and play a key role in night vision; responsive to dark and light contrast.
dark adaptation
process of adjustment to seeing in the dark.
cones
photoreceptors that are responsible for color vision and are most functional in conditions of bright light.
fovea
spot on the back of the retina that contains the highest concentration of cones in the retina; place of clearest vision.
visual acuity
the ability to see clearly.
optic nerve
structure composed of the axons of ganglion cells from the retina that carry visual information from the eye to the brain.
feature detectors
neurons in the visual cortex that analyze the retinal image and respond to specific aspects of shapes, such as angles and movements.
depth perception
the ability to see things in three dimensions and to discriminate what is near from what is far.
binocular depth cues
aids to depth perception that rely on input from both eyes.
monocular depth cues
aids to depth perception that do not require two eyes.
perceptual constancy
the ability of the brain to preserve perception of objects in spite of changes in retinal image when an object changes in position or distance from the viewer.
similarity
Gestalt law that says we tend to group like objects together in visual perception.
continuity
Gestalt law that says we see points or lines in such a way that they follow a continuous path.
proximity
Gestalt law that says we tend to group objects together that are near one another.
law of closure
The tendency to perceive a whole object in the absence of complete information.
bottom-up processing
idea that perception is a process of building a perceptual experience from smaller pieces.
top-down processing
perception of the whole based on our experience and expectations, which guide our perception of smaller elemental features of a stimulus.
trichromatic color theory
the theory that all color that we experience results from a mixing of three colors of light (red, green, and blue).
afterimages
visual images that remain after removal of or looking away from the stimulus.
opponent-process theory
the theory that color vision results from cones linked together in three pairs of opposing colors, so that activation of one member of the pair inhibits activity in the other.
Linear perspective
involves parallel lines that converge or come together the farther away they are from the viewer
Apparent motion
when were fooled into thinking something is moving
