Visual and Hearing study guide

Visual and Hearing study guide - Visual 1 3 2 4 Note image...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Visual Iris controls amount of light that hits the retina. The Lens- structure shape inverts image into retina. Retina – inner most layer of eye made up of different layers and cells in pic. (note sclera above retina). Fovea (macula) is the bump in back of retina and has densely packed light receptors. Fovea in direct line with visual access. Fovea specialized for high acuity vision. Photorecptors consist of Rods (code light as shades of light and dark) and Cones (code color). Cones are coded according to light spectrum- blue cones, red cones and green cones. Cones are packed together in fovea. Rods found mostly in periphery, and a few in center. Gangion cells respond to contrast. Pattern of stimulation across retina codes movement. Retina processes two types of contrast 1) lighter foreground, dark background (preferred by on center) 2) dark fore, and lighter back (preferred by off center). Visual processing of retina centered around antagonism- Ganglion Cell types – on center and off center. Horizontal cells - regulate firing of surrounding cells. (antagonism example- if area over center on in light then the center on cells fire and the surrounding cells are inhibited). Concepts of center surround antagonism 1) it’s a property of photoreceptors 2) Either excitatory for center + inhibitory for surround or opposite. 3) Photoreceptor will fire if field covered.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/02/2008 for the course SPH 262 taught by Professor Multiple during the Spring '08 term at University of Arizona- Tucson.

Page1 / 3

Visual and Hearing study guide - Visual 1 3 2 4 Note image...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online