Occipital Lobe

Question 1

What are two special things about the occipital lobe?

Answer 1

Boundaries between lobes is less visible

- contain double the density of cortical neurons

Question 2

What is the difference between damage in the striate cortex and secondary cortex?

Answer 2

Primary: loss of visual experience

Secondary: results in issues with perception (higher function). Translate assembled visual sensations from primary clortex into meaningful perceptions:

Damage to one hemisphere results in contralateral loss

Question 3

What are Scotomas?

Answer 3

• small areas of damage often result in localized islands or visual loss
• may be surrounded by regions of partial deficit (amblyopic)

Question 4

What does the tertiary cortex do?

Answer 4

Passed on from secondary to be intergated with information from other sensory modalities and cognitive data

Question 5

What is blindsight?

Answer 5

A condition whereby behaviour and decision based cognitions suggest vision is taking place but the patient says they are blind

• due to the tectopulvinar visual system that is associated with eye movement control

Question 6

What are some problems associated with secondary lesions?

Answer 6

Micropsia
Macros is
Porropsia
Pelopsia
Teleopsia

Question 7

What are the occipital lobe visual problems?

Answer 7

Visual spatial agnosia - results from intrahemispheric lesions affecting the corpus collosum that affects areas 18 and 19
- affects perception of death

Associative visual agnosia - resulting from deep lesions of occipital lobe
- patient can copy and draw objects but not name them or indicate use

Question 8

What areas in the occipital lobe?

Answer 8

Mainly primary and secondary visual cortex