Yes the mind. A truly wonderful organ of the body. I believe many impairments of the mind are strictly self-induced. I think to often the excuse of old age is used when let’s just say grandpa is sick of hearing his wife of 60 years nag him to take out the damn trash for the sixth time during the last 2 minutes of the Super Bowl. Good old grandpa just easily says I can’t remember things like I used to so he can selectively do whatever the hell he wants to.
Many scientists claim that the brain deteriorates with old age. But I think the test subjects in these studies are actually geniuses disguising themselves as forgetful old timers so they can get paid or a free lunch. Society mistreats our elderly way too much and they need this escape to just communicate with someone because their children have written them off because they don’t think any inheritance is coming. So you can argue that it is brought on my social conditions as well.
Other theories could easily be blamed on drugs and alcohol but I believe these people just listened to too much Tiny Tim and watched Teletubbies for extended amounts of time causing this brain deterioration.