Natural born killers?

We can all name famous psychopaths, be they the fictional Hannibal Lecter or real life Jack the Ripper. They can cause fear or uneasiness in even the most hardy of us. But what really makes a serial killer? Why are psychopaths so different from ‘us’?

The Horizon episode, Are you Good or Evil, examined the search for a so-called ‘moral gene’. At a fundamental level, humans are animals, so how did we come to possess morals, something other than instinct or self-motivation to guide our actions?

Paul Bloom and Karen Wynn designed an experiment to see if children were naturally born with a sense of morality or whether it was something they learned growing up. The experiment consisted of showing children a play with one ‘good’ character and one ‘bad’ character. When asked to choose a character, almost 70% picked the ‘good’ one, as most people presumably would.

But what about the 30% that were drawn to the bad character? Would they become bullies or ‘troublemakers’?

Another aspect of the show looked at military marines who were trained to fight, defend and, when necessary, kill. At a training base in the USA, marines are trained to act on instincts that have been drilled into them by years of training. This is necessary because when under pressure, they cannot afford to waste time reviewing actions; after years of discipline, the body reacts in the way it needs to, even if it means taking a life.

But one cannot ignore the idea of right and wrong. It is the reason why ex-soldiers returning from battle cannot readjust to society – they have lost their sense of morality and hold more than just the opposing army in contempt; they struggle to have empathy for anyone. As Captain Jack Hoban, a US Marine Corp, says “Humans are not natural born killers.” Psychologically, they cannot handle the idea of killing with morality, so they lose this sense all together.

However, not all soldiers are psychopaths. The Marines soon realised that instead of turning cadets into killers, they should turn them into ‘protectors’. Protectors would only kill when absolutely necessary; rather then remove their moral compass, they would ‘recalibrate’ it.

Both neurobiologists and psychologists have worked extensively into finding a chemical or gene that gives us our moral traits. Bob Hare is a psychologist who has looked particularly far into this field. On the outside, serial killers look normal and just like everyone else; no sign of self-inflicted wounds or grotesque disfigurements. Psychologically however, they seem to have a profound lack of empathy and an egocentric mind-set. They are not necessarily unemotional, but while emotions usually guide us to act, the psychopath feels no compulsion; they could very easily slaughter innocent victims, despite understanding the emotional impact.

In order to test this, Bob Hare brain scanned known serial killers using MRI while words were displayed on a screen. Monitoring the brain’s impulses, Hare noticed that emotional words trigger certain synapses for most people. In the psychopaths’ brains, there was indifference in responses to both emotional and regular words. Hare soon developed a ‘psychopathic checklist’ that tested things like personality, how you would react to certain situations and impulsivity.

Professor James Fallon, a psychologist working in the field of disorders like depression and schizophrenia, was asked to analyse a variety of PET scans to deduce the characteristics of the people to whom they pertained. One common theme emerged: the activity of two areas of the brain seemed to split the group, the orbital cortex and parts of the temporal lobe that surrounds the amygdala. These areas are known to control animal impulses and decision-making. All of the scans with damage in these areas came from serial killers. Was this the sole cause of psychopaths’ behaviour?

In 1993, one family was tested used genetic analysis. All of the males in this family had a background in violence and, interestingly, all of them had a mutation of the same gene sequence. The findings then showed that a variant of the MAO-A gene promoter (or ‘warrior gene’ as it became known), could also lead to psychopathic behaviour later in life.

Our brain chemistry and genetic mutations can reveal the traits corroborating with psychopathic behaviour. But will everyone with the genetic mutation become serial killers? The idea seems so wrong.

While visiting his family, James Fallon was asked by his mother to research his father’s relatives. He discovered that there was a lineage of violent killers in the family dating as far back as 1667. James decided to test his immediate family using PET scans. Only one brain showed classic psychopathic behaviour – his. Continuing further, he found that he had also inherited the ‘warrior gene’. Both characteristics were there and yet he was not a psychopath. He did have certain traits such as hot-headedness, lack of patience and at times, an uncaring attitude, all common amongst serial killers. This showed that the mind-set was there, but not at an extreme level.

Interestingly, the traits of psychopaths – impulsiveness, an uncaring demeanour and lack of pathos – can be found in professional jobs, such as CEOs and leaders of big corporations. Many of these people would rank highly on Hare’s checklist. It’s interesting how someone with a similar mind to a killer could work so well in business and society. Not that all bosses are psychopaths.

Fortunately, there emerged a third factor that ultimately determines your ‘destiny’: your childhood. If you have the genes and brain patterns, a nurturing childhood environment can reduce and even remove the risk of becoming a psychopath. Conversely, a damaging, dysfunctional, abusive childhood could trigger the aggressive genes. Your genes may lay the foundations, but your upbringing dominates who you will become.