Psychopaths are a misunderstood bunch. Some are evil, some are not – but to most, they seem to essentially be peculiar humans with unintelligible motives.
A new study by a Harvard University-led team has shed some light on the underlying causes of psychopathy. Explaining their findings in the journal Neuron, these researchers describe how they uncovered the neurological “wiring” that makes psychopaths so impulsive and sometimes dangerously reckless.
Although it’s previously been assumed that it’s their lack of empathy that engenders reckless choices and actions, this team have concluded that it’s the appeal of the short-term reward that’s really motivating their decisions.
“Because it's the choices of psychopaths that cause so much trouble, we've been trying to understand what goes on in their brains when they make decisions that involve trade-offs between the costs and benefits of action,” senior author Josh Buckholtz, an associate professor of psychology, said in a statement.
In order to achieve this, his team took a mobile brain scanner to 50 incarcerated prison inmates that had shown psychopathic tendencies in the past. While hooked up to the MRI machine, the prisoners were then given a “delayed gratification” test, wherein they had to decide whether to take less money from a pile sooner, or wait and get more money hours down the line.
The more impulsive and thus more psychopathic individuals required gratification far sooner, as expected. Individuals with high psychopathy scores showed greater activity in the region of the brain associated with immediate reward.

As they pondered on their decisions, the MRI scanners were looking at two key regions of the brain – one that is associated with “mental time travel”, which allows us to think about the future consequences of our actions, and one that is associated with more immediate decision-making.
The team found that the wiring between these two sections of the brain was far weaker in the more psychopathic inmates. Remarkably, the correlation between the strength of the wiring and the tendency towards impulsivity was so strong that they could use the brain scans alone to correctly predict how many times the inmates had been convicted of crimes.
Psychopathy is a poorly defined “condition”.
It’s not identifiable or describable by a sole characteristic; rather, it’s the tendency of a person to show a range of related traits and behaviors. These include a lack of empathy, an ability to become emotionally detached, a poor sense of self-preservation, has anti-authority proclivities, a lack of fear, and unconscientiousness.
Psychopaths are also more likely than others to be exhibit narcissism, just as they’re more likely to be Machiavellian (manipulative). When you think about it, capitalism is an ideal playground for ambitious psychopaths – climbing the social or career ladders without a thought to those pushed out of the way.
Still, none of these traits automatically make psychopaths “crazy” or “evil”, and in fact, although it does make those with high psychopathic tendencies appear to be somewhat ruthless and perhaps cold.
Frank Underwood: a machiavellian psychopath? Netflix via YouTube
Violent psychopaths can be both good and evil, so to speak – the example of James Bond and Dr. No are often cited in this case. Non-violent psychopaths have incredibly useful roles in society for the most part. Think negotiators, surgeons, spies, astronauts, mountaineers and, funnily enough, journalists.
As you can see, it’s complicated. Ultimately then, this study is something of a game-changer.
The team hope that by finding one clearly defined neurological driver of psychopathy, the definition of the condition becomes more scientifically rigorous and tangible.
It helps to highlights the fact that the brains of psychopaths aren’t unsolvable, impenetrable enigmas. They’re just wired differently, and that in itself doesn’t necessarily make them evil or monsters – it just makes them different.
“They're not aliens,” Buckholtz concludes. “They're people who make bad decisions.”