Why has Fallon been able to temper his behavior, while other people with similar genetics and brain turn violent and end up in prison? Fallon was once a self-proclaimed genetic determinist, but his views on the influence of genes on behavior have evolved. He now believes that his childhood helped prevent him from heading down a scarier path.
“I was loved, and that protected me,” he says. Partly as a result of a series of miscarriages that preceded his birth, he was given an especially heavy amount of attention from his parents, and he thinks that played a key role.
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.
Of course, there’s also a third ingredient, in addition to genetics and environment: free will. “Since finding all this out and looking into it, I’ve made an effort to try to change my behavior,” Fallon says. “I’ve more consciously been doing things that are considered ‘the right thing to do,’ and thinking more about other people’s feelings.”
Read more:
The Neuroscientist Who Discovered He Was a Psychopath | Surprising Science
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