Unit 3 (Part 1)

Cornea

protective covering of the eye

Pupil

adjustable opening in the center of the eye

Iris

the muscle that controls the opening of the pupil

Lens

transparent structure behind the pupil

Retina

contains of rods and cones/ inverts images

Accommodation

the process by which the eye lens changes shape to focus on near or far objects in the retina

Rods

detect black, white, and gray and are necessary for peripheral vision and twilight vision

Cones

concentrated near the center of the retina (fovea) and are involved in Foveal vision (opposite of peripheral vision), they function in daylight and well-lit conditions, they detect detail (acuity) and color; your central vision

Blind Spot

where the optic nerve leaves the eye

Foveal Vision

center of vision where details are sharpest (opposite of peripheral vision)

Peripheral Vision

what you can see from the corner of your eye

Feature Detectors

nerve cells in the brain (in the visual cortex) that respond to specific features of the stimulus, such as shape, angle, and movement

Hubel and Wiesel's Feature Detector Study

discovered it with cats in two different environments

Young – Helmholtz Trichromatic Theory

we have three types of cones in the retina that detect red, green, and blue. These colors are activated in different combinations to produce color

Opponent-Process Theory

sensory receptors in the retina come in pairs. If one sensor is stimulated, then the other is inhibited from firing (explains afterimages and color blindness)

Pairs: Red/Green, Yellow/Blue, Black/White