Perception and Color Vision Lecture Flashcards

Vocabulary flashcards defining key sensory, retinal, and psychological terms related to light detection and color vision theories based on the lecture notes.

Photoreceptors

Neurons or nerves in the eye that fire in response to light and act as sensory receptors.

Fovea

The specific area of the retina where photoreceptors are most tightly packed, allowing focused light to be processed in high detail.

Optic Nerve

The structure exiting the inside of the eye through the retina, creating a spot that lacks photoreceptors and receives no visual information.

Rods

Photoreceptors that are sensitive to black and white, do not perceive color, and do not provide fine detail.

Cones

Photoreceptors that function best in bright light, respond to color, and provide detailed visual information.

Peripheral Vision

Visual processing outside direct focus that effectively detects movement, contours, and shadows, but provides little color or detail.

Top-down Processes

Cognitive processes that fill in color and visual detail across regions outside the fovea by relying on memory and stored information.

Trichromacy Theory

The explanation of color perception based on three cone channels attuned to blue, green, and red, which together allow humans to distinguish between 7 to 10,000,000 different colors.

Just Noticeable Difference

A test or measurement of color vision used to determine whether two presented colors are perceived as the same or different.

Color Blindness

A visual condition caused by missing one of the three color channels—occurring in about 20% of men—where an individual sees fewer colors rather than no color at all.

Pentachromats

Entities that possess five distinct color-sensing channels.

Opponent Processes

A neural mechanism where color information is combined into opposite channels—black versus white, red versus green, and blue versus yellow—preventing opposing colors from being perceived simultaneously through the same channel.