parts of the eye and more about the eye (psych soldano)

cornea

clear outer covering of the eye

aqueous humor

fluid that nourishes the eye

pupil

black circle in the middle of the eye that changes size as the iris muscles move to cover and uncover the lens

iris

coloured circular muscle that opens and closes for the amount of light

lens

transparent structure that focuses light on the retina (acts like a camera lens)

vitreous

liquid that nourishes and gives shape to the eye

retina

back part of the eye with millions of receptors for light

rods

visual receptors for black and white

cones

visual receptors for colour

fovea

central area of retina with the greatest density of photo receptors

blindspot

portion of the retina through which the optic nerve exists and where there are no receptors of light

optic nerve

where nerve cells leave the eye and give information to the brain

visual accommodation

monocular cue of depth perception, the brain use of info about the changing thickness of the lean of the eyes in response to looking at objects that are close or far

presbyopia

lens hardens through age; loses ability to focus

myopia

nearsightedness; focal point falls short of the retina

hyperopia

farsightedness; focal point falls behind the retina

visual activity

keenness or sharpness of vision

trichromatic theory

3 types of cones; red, blue, and green (everything we see is a mix of these colours)

opponent process theory

visual neruons are stimulated by light of 1 colour and inhibited by light of another colour

after image

image remains after stimulation of the retina is over

colour blindness

inability to see certain colours