- Psychopaths sometimes have a genetic predisposition that makes them the way they are.
- There are some biological differences in the brains of psychopaths compared to the general population.
- Other research suggests that it is someone's upbringing that has an impact on whether they become a psychopath.
- It's likely to be a mixture of nature and nurture that turns someone into a psychopath, and they're likely to use both to their advantage to manipulate others.
Psychopaths are thought to make up about 1% of the population, and an even higher percentage of people have psychopathic, narcissistic, and sociopathic traits, such as an inflated sense of self or a lack of emotion.
Whether psychopaths are born or made over time, though, is a grey area.
Some scientific literature suggests there is a strong genetic component to these traits.
The genes that make us unfeeling or narcissistic are often selected in evolution because they have benefits, especially if you are a in a profession where a cool head is paramount. A higher than average amount of CEOs tend to be psychopaths, for instance.
Perpetua Neo, a therapist and specialist in dark triad personality types, told Business Insider: "Evolution doesn't care about how altruistic you are, or how much good you do."
"Evolution only cares that the genes are passed on and they fit a certain environment. So because of that, it can't really weed out psychopaths and narcissists."
Because of this, these genes are likely to always persist in the population. So, instead of focusing on attempting to fix people, Neo says it is better to teach people how to recognise red flags for psychopathic behaviours, heal ourselves from any predispositions on being attracted to them, and run "fast and far."
Genes aren't our destiny.
According to James Fallon (Jim in the photo), a UC Irvine School of Medicine neuroscientist who accidentally found out he may be a psychopath himself, some genes may be biologically visible. In his research he found that many psychopaths show distinctive patterns of brain activity.
He used MRI scanners to examine the brain activity of dozens of people thought to be psychopaths, and found that there tended to be reduced activity in the areas that play roles in regulating emotions, impulses, morality, and aggression.
However, Neo says your DNA isn't the deciding factor in everything. The same genes in different people can be expressed differently thanks to something called epigenetics. Also, negative behaviours can be learned — or even rewarded — in childhood, leading to them being practised more often.
For instance, sometimes children are brought up with a psychopathic or narcissistic parent. In these cases, the child may grow up thinking they can only get attention and resources by being manipulative.
A study in 2013, published in the European Journal of Psychotraumatology, explored the relationship between early childhood neglect and abuse, and the likelihood of scoring higher on the psychopathic scale.
The researchers assessed 22 offenders convicted of violent crimes aged 22 to 60, and used the "Traumatic Experience Checklist" to analyse the level of childhood relational trauma they had experienced. This information was then compared to where the offenders landed on the psychopathic scale, using the "Hare Psychopathy Checklist," developed by criminal psychologist Robert Hare.
The team concluded that psychopathy may be linked to a history of trauma, particularly in the more severe violent offenders.
Another study, published in the journal Psychological Medicine, examined 333 males and females to see how maternal and paternal bonding and childhood physical abuse had an impact on developing a psychopathic personality at age 28. It also looked at whether children separated from their parents in the first 3 years of life were more likely to be psychopaths 25 years later.
The researchers found that disrupted parental bonding was associated with an increased level of adult psychopathy, with a lack of maternal care being the most important aspect.
"Childhood physical abuse was also associated with psychopathy, but evidence from regression analyses suggests that bonding is more primary than abuse," the researchers wrote. In other words, neglect at a young age appeared to have more of a connection with an adult psychopathic personality than being physically assaulted as a child.
Trauma is a sliding scale.
Parents divorcing could also have an impact on whether psychopathic traits become more pronounced. Disruptive experiences like divorce could generate symptoms of Post Traumatic Stress Disorder on par with "big T" trauma events such as abuse, according to one study published in the British Journal of Psychiatry.
Neo said that children who take on these experiences sometimes deal with them by becoming manipulative and learning how to play parents off against each other.
"Some kids, they know how to cry at the drop of a hat, and smile when they get their way," Neo said. "And the things that they say to play one parent against another, or one parent against an individual, is really well orchestrated."
However, that's not the full story. Other children are predisposed to acting a certain way, regardless of their parental situation or how they were brought up.
"There was this study that I read about this subsection of kids who are extremely cruel, and extremely deviant," said Neo. "From a young age, psychopathic children tend to torture animals for fun."
"We've all done things like catch a dragon fly, or a cockroach, but you read stories about how pre-psychopathic children do things like kidnapping dogs or cats, and slowly dissecting them alive, just to see what's happening," Neo added.
"They do it with this cold, detached ability that you don't see in normal kids who have empathy."
One case study, reported in The Atlantic, involved a child called Samantha (a fake name), who began exhibiting some worrying behaviours at about age six. She made a "book about how to hurt people" which included drawings of murder weapons like knives, poison chemicals, and a plastic bag to be used for suffocation.
Samantha was adopted by her parents at age two, who already had five biological children of their own. When one of their youngest children was still a baby, Samantha tried to strangle him, just to see what would happen.
"People with such obvious psychopathic, callous behaviours at a young age, after repeated incidents in a family, tend to be institutionalised," Neo said. "But those who learn to not have such extreme behaviours — they trickle down through the cracks."
Over time as they grow up, these people find themselves in certain environments which reward their psychopathic traits and behaviours, according to Neo.
"Their psychopathic behaviour muscles or narcissistic behaviour muscles get stronger, and it becomes wired in them as a pattern of being, and it becomes a personality," she said.
The answer isn't simple.
Where nature or nurture is more of a factor in becoming a psychopath is not fully understood, and much of the research in the area points out the need for further study.
What is known is how psychopaths manipulate the people around them. Neo says they are often familiar with the fact they have had a troubled past, and they use this information to get people to do what they want.
For example, it can be incredibly hard to cut psychopathic people out of our lives, because we know they have had a tough time,so we feel sorry for them.
"Unfortunately, they do not empathise with us," Neo said. "Their main modus operandi is 'How do I get the kicks out of hurting someone?' or 'How do I get this attention out of making someone suffer?" So inherently, this relationship you have — whether it's romantic, friendship, or otherwise — is asymmetrical.
Join the conversation about this story »
NOW WATCH: The 9 coolest signatures of famous people throughout history