Peripheral Vision

[Somski]

Why is it that some types of brain surgeries can cause problems with peripheral vision only? what part of the brain specifically controls peripheral vision?

[Peter Pedant]

First part: There are specific pathways and tracts leading from the retina via the optic nerve to the back of the brain. They also cross. The tracts are not mixed and so if you nick the bit at the crossing near the X, one nick can affect the both tracts, and it so happens that it is the outside part, on both sides. Strange but true. Any scientific explanation needs to use the words somatotopic representation - which is bit technical for AB.

Second part. This question has no meaning. Read a text book on human physiology - Ganong, any edition after the tenth. The chapter on vision, it will have pictures showing why part 1 is true.