The brutal crimes of serial killers are regularly considered to be evil, but what makes one person evil and another not? Neuroscience is becoming increasingly focused on the brains of serial killers and psychopaths in order to assess how they may be different and whether these differences can go some way to account for their violent criminal behaviour.
The theory is simple; if we knew what caused evil then maybe we could develop a way to stop it. Dr Jonathan Pincus, who was Chief of Neurology at the VA Hospital in Washington DC. In this role he conducted extensive studies into the causes of violent behaviour and why people kill, developing a theory where such behaviour can be reduced down to three main factors; abuse, brain damage and mental illness.
Serial Killer Brain vs Normal Brains
Previous research has indicated that childhood abuse could be a factor in psychopathic killers. There is evidence that John Wayne Gacy, the ‘Killer Clown’, Gary Ridgeway, the ‘Green River Killer’ and Ed Gein, the notorious American serial killer, all suffered abuse as children which may have impacted their violent behaviour as adults.
Another key figure in the hunt for biological factors which may be involved in why people kill is Dr Adrian Raine. A psychologist and academic, he has spent much of his career studying the neurobiological and biosocial factors involved within antisocial behaviour.
His work has covered both children and adults highlighted in his book ‘The Anatomy of Violence – The Biological Roots of Crime‘. In his most notable study to date, he scanned the brains of convicted murderers and compared the results against the brains of everyday people.
By arranging for 41 inmates to be brought to his lab to participate in the study, he injected them with a glucose isotope which would show during the scanning process, highlighting the brain patterns of that individual.
What he found were differences in the brains of these convicted murderers compared to the brain patterns of non-violent individuals. Primarily these differences could be seen in the frontal lobe of the brain that sits behind our forehead; the pre-frontal cortex. This is the area which deals with impulses, decision-making and rationale.
The brains of those who were serial killers showed distinct patterns of brain activity which were different from normal brains and from impulse murderers’ brains. An exciting finding however, there are many people who have brain scans which are closer to the serial killer group than to the normal group for example, but that does not mean they are serial killers. This research therefore, is far from conclusive.
In our quest to understand what causes the extreme violence often seen in serial murder, the idea that brain damage and mental illness can impair judgements and impulses while a history of childhood abuse can fuel rage, is a theory which is still undergoing investigation.
Moreover, the brain scanning of serial killers is still in its infancy. A great deal more research is needed before any firm conclusions about brain differences and biological factors being the cause of such violent behaviour can be drawn.