Serial killers have many frightening sides. The scariest thing about them is that experts still don't know what causes a human to become a serial killer. Many experts believe that serial killers become who they are because they have a genetic predisposition or brain abnormality, while other experts believe that a serial killer is created by the abuse suffered during childhood ; and other experts believe it is a combination of brain abnormalities and abusive childhood experiences that creates a serial killer. A murderer is considered a serial killer when he or she "murders three or more people in at least three separate events with a 'cooling off period' between the killings" (Mitchell and Aamodt 40). When defining a serial killer, their background, genes, and brain are not mentioned; maybe one day these aspects of the serial killer can be included. Many studies suggest that there are significant differences in the brain between individuals with antisocial personality disorder (psychopathy). Although not everyone with antisocial personality disorder will become a serial killer, all serial killers studied have antisocial personality disorder; “Neuropsychological tests revealed abnormalities in all test subjects” (Blake, Pincus and Buckner 1642). Brain damage, brain abnormalities, or mental illness affects all serial killers tested. Even if all serial killers had some sort of abnormality in the brain, would that mean they were doomed to become serial killers? According to experimental results discussed in Neurologic Anomalies in Murderers; 64.5% of serial killers have frontal lobe dysfunction and 29% have temporal lobe abnormalities. The brain's frontal lobes "control the essence of our... middle of article ......f brain abnormalities on psychosocial development, criminal history, and paraphilias in sexual murderers." » J Forensic sci 50.5 (2005): 1204-8. Culter, Mary Ann, Joanne Dombrowski, Michael Doughtery, Paula Henderson and Laura McNicholas “The brain: understanding neurobiology. NIH Publication, March 20120.April 21, 2014. Miller, Laurence. “The predator’s brain: neuropsychodynamics of serial killers.” » Serial Offenders: Current Thinking, Recent Findings, Unusual Syndromes (2000): 135-166.Mitchell, Heather, and Michael G. Aamodt. “The Incidence of Child Abuse Among Serial Killers.” » Journal of Police and Criminal Psychology 20.1 (2005): 40-47. Raine, Adrian, Monte Buchsbaum, and Lori LaCasse “Positron-Indicated Brain Abnormalities in Murderers.” emission tomography." Biological psychiatry42.6 (1997): 495-508.