While studying brain scans for a research project he was working on, he discovered that his own brain scan displayed all the features of a psychopath. It wasn’t just his brain scan. He also discovered he had the genetic markers for aggression, violence and low empathy – all features of a psychopath. He also had the inclinations of a psychopath and he had a family history with seven alleged murderers. Yet, despite the odds against him, James Fallon is a happily married man who has never raped or killed anyone.

What protected him from the dark path? James Fallon attributes it to his loving childhood experiences.

“I was loved, and that protected me,” he says.

This corresponds to recent research: His particular allele for a serotonin transporter protein present in the brain, for example, is believed to put him at higher risk for psychopathic tendencies. But further analysis has shown that it can affect the development of the ventromedial prefrontal cortex (the area with characteristically low activity in psychopaths) in complex ways: It can open up the region to be more significantly affected by environmental influences, and so a positive (or negative) childhood is especially pivotal in determining behavioral outcomes.