... Clearly your father has seen good doctors so I guess that's a comfort. But even good docs sometimes have trouble diagnosing unusual things. And in your fathers case it might be that his symptoms are less when he's actually being tested. ... (3 replies)

... extreme dizziness. It starts when he gets out of bed in the morning and gets progressively worse. There are times he has to stop what he is doing bc his eyes are bouncing up and down so bad. ... (3 replies)

... Check out this article by Timothy C. Hain, MD: http://www.dizziness-and-balance.com/practice/saccadic-nystagmus.htm (2 replies)