dementia

my dad is 88 and I have taken him to his Dr. who's idea of a dementia test is who is the president and what is the date.  His cat scan didn't show any brown spots on it, but his personality is swinging from anger to happy.  His wife is in the hospital for spin surgery and he is thinking that her family wants to "take over", when he's been the one to take her to med appt. etc.  Is he just being controlling or do I need to be worried?  He has been controlling most of his life, but is becoming more so. Like telling me how to drive home.  Thanks

[Roger Gould, M.D.]

As people get older,some of their core characteristics become greatly exaggerated, and this is a psychological phenomenon, not a brain issue. Unless there are other signs of dementia, that is probably what is happening.