Home > Neurologic Disease > Loss of Moral Reasoning in FTD Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Oct 26, 2008 by BMiller, Views: 3707 Frontotemporal Dementia, FTD, affects the frontal lobe of the brain. The frontal lobe is the area of the brain that controls moral reasoning. When patients develop Frontotemporal Dementia they can carry out illegal activity that they would have never previously even thought about. They lose their normal sense of self. Dr. Bruce Miller, the Director of the Memory and Aging Center at UCSF, discusses frontotemporal dementia.