Mod7-Obj5: Visual pathway to the visual cortex of the occipital lobe

Question 1

Visual pathway to the brain (action potential)

-7 processes

Answer 1

1. ) Retina
2. ) Photoreceptor cells
3. ) Axons of retinal ganglion cells form optic nerve (cranial nerve II)
4. ) Medial fibres of optic nerve cross over at optic chiasma
5. ) Most fibers of optic tracts continue to the thalamus
6. ) Optic tracts (radiations)
7. ) Projections to primary visual cortex in occipital lobes

Question 2

Cortical processing

Answer 2

1. ) Primary visual cortex
   - Conscious perception of visual images
2. ) Visual association areas
   - Interprets visual inputs

Question 3

Visual pathway

Answer 3

Two optic nerves cross at the optic chiasma to the other side.

• Medial fibres of each optic nerve cross.
• Lateral fibre stay on the same side
  e. g.) Impulses from the right half of each retina travels to the right visual cortex

Question 4

Depth perception

Answer 4

Overlapping images (slightly differ)

• The combined view of 2 eyes provides binocular vision (allows depth perception)
• Visual cortex fuses the 2 slightly different image to provide depth perception