WASHINGTON (WUSA) -- What would make a graduate student in neuroscience carry out the horrific attack in Aurora, Colorado? 

Dr. Mary Ellen O'Toole is a former FBI profiler who spent her entire career studying criminal minds. She says although many people say this is a case of someone simply snapping, that: 

"...this is not the kind of behavior where someone just snaps. This is behavior that indicates a great deal of planning that probably went back days if not months, and the planning was very detailed and it's very analytical. It's just the opposite of someone who wakes up that morning and gets all the items that they need to carry out an assault like this, absolutely not. This shows some very comprehensive planning."

See what else she had to say about the mind of the suspect and the planning of the attack in the video above.