Anti-social personality disorder is an affliction that many people will argue is caused by either nature or nurture, but in my opinion it is nature that causes people to develop this disorder. Anti-social personality disorder is defined as "a personality disorder in which the person (usually a man) exhibits a lack of conscience for wrong-doing even towards friends and family members. This may manifest itself in a number of ways, some of these manifestations may be aggressive and ruthless behavior or being deceitful like a clever con-artist." (Psychology sixth edition, G-1) .
Anti-social personality disorder can be traced to the genes of the people who suffer from this affliction. In a study conducted in 1995 it was discovered that twins and adopted siblings are at increased risk of criminality (psychology sixth edition, G-1). In another study conducted by Hare in 1975 and published in 1978, when people suffering the disorder were exposed to electrical shock or loud noises they showed little automic nervous system arousal. (Psychopathy and differential insensitivity. In R. Hare & D. Schalling (Eds.), Psychopathic behavior).
The brain is wired according to genetic coding. In 1999 a study conducted by Adrian Raine compared the brains of 41 murderers with the brains of people who did not commit crime and were of the same sex and same age. Raine was astonished to find that the killer's frontal lobe exhibited reduced brain activity. This part of the brain is vital because it helps control impulses. Having the frontal lobe damaged has proven to affect people's knowledge of right and wrong as was revealed in the famous case of Phineas Gage. Phineas Gage was a construction worker who in 1848 succumbed a blast that left a rod through the frontal lobe of his brain. He was operated on and the rod was removed but it damaged the frontal lobe of his brain. After this horrific accident and surgery Gage's attitudes changed and he began to act erratic.
