The debate over “nature versus nurture” has existed since the sixteenth century. Are people genetically predisposed to behaving a certain way, or are our environments– such as life events– responsible for molding us?
This age-old question has been debated everywhere, from college classrooms to psychologists’ offices.
But, a study conducted by researchers at the University of Glasgow sought to specifically probe this debate among criminals. More specifically, serial killers and mass murderers.
The study was the first of its kind to analyze all available records– including legal files, news reports, books, and journals– about this criminal niche and attempt to conclude why both serial killers and mass murderers commit such heinous acts.
The researchers specifically studied the various psychosocial and neurodevelopmental risk factors among two hundred and thirty-nine killers.
And the team found that the criminals’ tendencies to resort to such extreme forms of violence were the product of a complex interaction of sociological, psychological, and biological factors. In other words, both nature and nurture.
However, the team also uncovered two specific commonalities among the killers.
“Potentially, a significant proportion of mass or serial killers may have had neurodevelopment disorders such as autism spectrum disorder (ASD) or head injury,” the report reads.
Of the killers analyzed in the study, twenty-eight percent were deemed to have had either “definite, highly probable or possible” ASD. Additionally, about twenty-one percent suffered from a suspected or definite head injury.