A Vanderbilt University study has new findings on how psychopaths weigh risk and reward. The study suggests that psychopaths may possess amped-up dopamine reward systems that compel them to pursue their goals regardless of personal cost.
Study co-author David Zald notes that previous studies of psychopathy focus on the personality traits of psychopaths rather than the way psychopaths assess incentives:
There has been a long tradition of research on psychopathy that has focused on the lack of sensitivity to punishment and a lack of fear, but those traits are not particularly good predictors of violence or criminal behavior [...] Our data is suggesting that something might be happening on the other side of things. These individuals appear to have such a strong draw to reward — to the carrot — that it overwhelms the sense of risk or concern about the stick.
In this National Institute on Drug Abuse-funded study, volunteers were given amphetamines (a.k.a. speed!) and then subsequently had their brains analyzed. As psychopathy is often correlated with drug abuse, those who displayed traits of psychopathy released four times the amount of dopamine in response to the amphetamines. A second part of the study analyzed how volunteers' brains reacted to a promise of a monetary reward. Again, those with the psychopathic traits released heightened amounts of dopamine.
Sadly, the study did not delve into whether or not psychopaths produced more dopamine while listening to the music of Huey Lewis and The News.
You can find the full study at Nature Neuroscience.