Visual Pathways Flashcards
Where are ganglion cell receptive fields smallest?
At the fovea
Get larger as you move outwards
What photoreceptors are found in the fovea?
Just cones
What is seen in optic chasm lesion (eg crushed by pituitary tumour)
Bitemporal hemianopia
Lose half of vision on temporal sides
What is seen in a right hand side optic tract lesion?
Homonymous hemianopia
Lose half if vision, in left half of each eye
Explain why macula sparing can occur
Blood supply- The arteries may not be effected by what caused the lose if vision
If you fall backwards on your head and damage that part if the brain- where may vision lose be?
Where the macula is
How many layers are in the lateral geniculate nucleus (thalamus)?
6
What is the functional unit of the cortex?
Columns
What cells are found in layers 1 & 2 of the lat gen nuc?
Magnocellular
What cells are found in layers 3-6 of the lat gen nuc?
Parvocellular