Question

Interruption of the visual pathway in the 

A. Left optic tract causes blindness in the right visual field (right homonymous hemianopia). 

B. Optic chiasma causes blindness in the nasal half of each visual field (binasal hemianopia). 

C. Left optic radiation causes loss of vision to the right. 

D. Occipital cortex causes loss of the light reflex. 

E. Occipital cortex causes loss of central vision with preservation of peripheral vision.

Answer 1

A. True The left half of each retina is concerned with vision to the right and impulses from them travel in the left optic tract. 

B. False The crossing fibres come from the nasal half of each retina and are responsible for temporal vision; bitemporal hemianopia results. 

C. True As with damage to the left optic tract. 

D. False This is a brain stem reflex. 

E. False The reverse is true because the fovea is bilaterally represented in the cortex.