All Flashcards
What is the key idea about color perception?
Perception is an active process, not a passive recording of reality.
What is the Young-Helmholtz trichromatic theory?
Retina has red, blue, and green color receptors that combine to make all colors.
What is the opponent-process theory?
Color vision depends on opposing processes: red-green, blue-yellow, white-black.
Explain colorblindness in terms of color receptors.
Lack of one or more color receptors (monochromatic or dichromatic).
What is dark adaptation?
Eyes adjust from cone vision to rod vision in the dark, becoming more light-sensitive.
What is the function of feature detectors?
Cells in the visual cortex respond to specific features like lines, angles, and movement.
What is the cause of the blind spot?
Where the optic nerve leaves the eye; no receptor cells are present.
What is the function of supercell clusters?
Teams of cells in the visual cortex that respond to complex patterns.
What is nearsightedness (myopia)?
Blurry distance vision due to too much cornea curvature.
What is farsightedness (hyperopia)?
Blurry near vision due to too little cornea curvature.
What is astigmatism?
Distorted vision due to an irregular cornea or lens shape.
What is the effect of short vs. long wavelengths on color perception?
Short wavelengths = purple; long wavelengths = red.
What is the effect of different light intensities on the pupil?
Bright light = small pupil; dim light = large pupil.
What causes the blind spot, and why don't we notice it?
Optic nerve leaves the eye; brain fills in the gaps.
What is the effect of lacking certain color receptors?
Colorblindness (monochromatic or dichromatic).
What is wavelength?
Distance between wave peaks/troughs; determines hue (color).
What is amplitude?
Height of a wave; determines intensity (brightness).
What is hue?
The color we perceive, determined by wavelength.
What is intensity?
The brightness of a color, determined by amplitude.
What is the cornea?
The eye's protective outer layer that bends light to focus.
What is the pupil?
An opening in the eye controlled by the iris that adjusts to light intensity.
What is the iris?
A muscle that controls the size of the pupil.
What is the lens?
Focuses light onto the retina, changing shape through accommodation.
What is the retina?
Where transduction happens; contains rods and cones.
What are photoreceptors?
Rods and cones in the retina that transduce light energy.
What are rods?
Photoreceptors for peripheral vision, black/white/gray, dim light.
What are cones?
Photoreceptors for central vision, color, fine details, bright light.
What is the optic nerve?
Carries visual signals from the retina to the thalamus.
What is the optic chiasm?
Where optic nerves cross, sending information to opposite hemispheres.
What is transduction?
Conversion of sensory stimuli into neural impulses.
What is accommodation?
The lens changing shape to focus on objects at different distances.
What is parallel processing?
Brain divides visual scenes into aspects and works on them simultaneously.