Following up on the
New Republic article posted by Monkfish, I thought I would post an article from the same magazine on a devastating neurological disorder known as Frontotemporal Dementia (FTD) that destroys a portion of the brain that affects moral behavior, resulting in loss of compassion and loss of inhibition.
FTD is ugly. It blunts compassion and it lowers inhibition, leaving patients spouting racial slurs in public and cheating on their spouses. When self-control and self-restraint go, patients are left unlike themselves. It tends to hit earlier than Alzheimer’s, usually between someone’s 40s or early 60s, and there’s a large genetic component. Family history is the only known risk factor for the disease—it’s inherited in a third of all cases.
“In the lab, researchers will ask patients in the early stages of this disease 'Is it okay to laugh at someone who fell down?' or 'Is it okay to steal a wallet?' or 'Is it okay to speed on the highway?" and usually they will be able to say 'No, that’s wrong.' But the fact is, outside in everyday life, they’re doing these things anyway,” Wanucha told me. “What that says to me is that they may still understand right or wrong, but they don’t care on an emotional level. They no longer care about the impact of their behavior on other people. They no longer care about how their behavior reflects back on them through other people’s eyes." Of course, this ability to step back and reflect on our actions—to see them as others see them—is one thing that separates us from most, if not all of our primate relatives. It's part of what makes us who are we.
“Because of brain damage, they’ve lost this ability that they used to have to apply this emotional, intuitive knowledge about how they should act and put that into practice,” she went on. “I think that’s an important distinction to make because someone with FTD is not choosing to act this way, and these people—who used to be teachers, artists, athletes—can get into a lot of personal, legal, or financial trouble if others don't take responsibility and look out for them."
http://www.newrepublic.com/article/1...or-your-memory
I know people with Alzheimers, but not with FTD. I can't imagine how difficult it must be for their family members.