I planned at one time to get a general aviation license in the early 1990s, and I passed ground school, got cleared for everything, but did not have the money and time to complete the 40 hours flight time with instructor within the 2 years allowed, so I'll have to start over if I decide to go for it again. At that time, the only medical exam issues to stop anyone from getting their medical clearance was the regular physical; heart, blood pressure, etc. You can't have a history of seizures or epilepsy, or perhaps other physical problems which obviously might cause you to suddenly be unable to control the plane, but there were no psychiatric questions that I recall. Nowadays, I heard that you have to prove US citizenship and have no criminal record for drug trafficking, etc., and are not of any affiliation with a fundamentalist group or terrorism.
Charles