WAS one of the best neurosurgeons with possibly the largest ego to suit (or to boot).
At this point I believe he is suffering from a mild dementia, possibly a degenerative form. I see memory deficits and even confabulation. In addition his typically flat affect and speech patterns are very unusual in a highly accomplished person.
He does indeed seem to be a little.....slow.
(before flaming - I have no horse in this race just yet)
I cannot help but wonder about exposure to prions.