The mystery of the Vegas shooter's brain

It is important to note that a tumor isn’t the only thing that can cause such changes in behavior: strokes or a traumatic brain injury can do the same. And one disorder in particular deserves mention: frontotemporal lobar degeneration (FTLD). Although the name is long, this simply refers to a deterioration of two lobes of the brain, the frontal and the temporal: two regions that underpin much of the decision-making and emotion that makes us social creatures.

As these brain areas degrade, people develop frontotemporal dementia (FTD) — and this often comes hand-in-hand with violent, asocial behavior. When I heard Paddock’s age, I immediately began to wonder about this, as the onset of the disease is typically in a person’s late 50s.