AP Psychology - 4.2

How does your brain make sense of colors, shapes, depth, and movement?

by putting the information together like a jigsaw puzzle - into something coherent

How do optical illusions work?

by exploiting the mind's tendency to try to find order in patterns (tapping into it's stored information)

Light

• stuff that triggers visual sensations; described in terms of wavelengths

  • The hue (color) we perceive in light depends on its wavelength, while its intensity (brightness) depends on the light wave's amplitude

Cornea

transparent tissue forming outer surface of eyeball; light 1 st passes through this into your fluid-filled eye

Iris

colored part of the eye; muscle that determines amount of light that passes through pupil

Pupil

the black opening in the iris; size adjusts automatically to the amount of light; is also sensitive to emotional response

Lens

• transparent body behind the iris/pupil that focuses an image on the retina; adjusts to an image by changing its thickness

  • When people squint to focus near or far, they are adjusting the thickness of the lens (accommodation)

Nearsightedness & Farsightedness

Nearsightedness: occurs when the lens focuses objects in front of the retina

Farsightedness: occurs when the lens focuses objects behind the retina

Retina

light sensitive photoreceptor cells and layers of neurons that begin processing visual information

Fovea

area of central focus in the retina; just above optic nerve; cones cluster in & around it

What are the Millions of retinal photoreceptor cells that convert light energy into neural impulses sent to the brain by?

optic nerve

Optic nerve

a bundle of axons from a specific type of cells called ganglion cells