Class Notes (1,100,000)
CA (630,000)
UTSC (30,000)
Psychology (8,000)
PSYB65H3 (500)
Ted Petit (300)
Lecture

Visual System


Department
Psychology
Course Code
PSYB65H3
Professor
Ted Petit

This preview shows pages 1-2. to view the full 6 pages of the document.
Human Brain and Behaviour
Visual System
Anatomy
How is it organized
Everything begins in the retina
oRetina is part of the central nervous systemNOT PERIPHERAL
oRetina grows out from the brain—so it is part of the brain
oRetina is divided right down the centre into two parts
The part near the nose is called the NASAL PORTION
Part close to the outside of your head is called TEMPORAL
PORTION
Information from each half
oA nerve is a pathway outside the central nervous system (peripheral system)
oFor pathway in the Central nervous systemITS CALLED A TRACT
oEverything close to the eye is called the OPTIC NERVE
oNerves from the eye crossover (some crossover, some dont)
Cross over is called OPTIC CHIASM
When it moves towards the brain the nerves are call TRACTS
After optic nerves
When nerve fibers come together at optic chiasm
oFibres from temporal portion of the retina come together at optic chiasm
BUT DO NOT CROSS
oFibers from nasal portion of the retina come together and cross.
oSomething in your RIGHT visual field will hit the NASAL PORTION of
RIGHT EYE and TEMPORAL PORTION of LEFT EYE
www.notesolution.com

Only pages 1-2 are available for preview. Some parts have been intentionally blurred.

oInformation from right visual field cross over and ends up in LEFT cortex
Everything that you see is your VISUAL FIELD
oIf Im looking at Petit and hes in the centre (IM LOOKING STRAIT
AHEAD)Everything to the right of him is my RIGHT HALF FIELD
(usually said Right Field)
WHAT HAPPENS AT EACH LEVEL OF ANATOMY
What the brain processes
The way the nervous system works—the farther from the brain the more simple
things are
oRetina is first entrancegets excited because a single beam of light hits a
receptor field
Neurons in receptor can only analyze LIGHT or NO LIGHT.
When we get to Area 17 (in the cortex)respond to line of a particular
orientation
When you get to Associational Cortex, can respond to more complex
recognition—can recognize shapes or faces
The problem that you get in a patient behaviourly is related to where
the damage is
Retinaproblem is not as complicated
Area 17more complicated
Association complex—A very serious problem
Damage at occipital cortex(usually a huge stroke—POSTERIOR
CEREBRAL ARTERY)—youll get complete blindness
If you get partial damage in the cortex—blindness in opposite visual
field
Macular Sparingnot complete blindness, small spot where you can
see in that cortex
Scatomasmall of blindness caused by a small area of damage
www.notesolution.com
You're Reading a Preview

Unlock to view full version