Visual System

Question 1

What is the function of the visual system?

Answer 1

• It takes information from the eye to the brain so we can see our environment.
• Allows us to interact with the world, recognise objects, navigate and perform tasks that rely on visual input.

Question 2

What % does the visual system make up of the sensory system?

Answer 2

70%.

Question 3

What is binocular vision?

Answer 3

Refers to the eye’s position causing a fixated object to fall in exactly the same spot on both retinas.

Question 4

What is a visual field?

Answer 4

Refers to the shape of the retina receptors and how they are oriented to see certain parts of the environment.

Question 5

What 2 visual fields can the environment be broken down into?

Answer 5

• Right visual field.
• Left visual feild.

Question 6

What detects the right visual field?

Answer 6

Detected by the left temporal and right nasal retina.

Question 7

What detects the left visual field?

Answer 7

Detected by the right temporal and left nasal retina.

Question 8

Outline the step-by-step process of how the visual system functions.

Answer 8

1. SAN receptors and cell bodies lie in the retina.
2. They travel via the optic nerve and chiasm to the thalamus, where they terminate.
3. Information received by the temporal retina always stays on the same side.
4. Information received by the nasal retina always switches sides and crosses to the contralateral side.
5. The crossing of the nasal retina is known as partial reorganisation.
6. TAN receptors and cell bodies are located in the thalamus.
7. They ascend up to the primary visual cortex in the occipital lobe.