In response to a question about sociopaths.
When people talk about sociopaths they are usually referring to people who have been, or could be, diagnosed with an Antisocial personality disorder. To receive this diagnosis, at least three or more of the following are required (according to the DSM IV-TR):
1. Failure to conform to social norms with respect to lawful behaviors as indicated by repeatedly performing acts that are grounds for arrest.
2. Deceitfulness, as indicated by repeatedly lying, use of aliases, or conning others for personal profit or pleasure.
3. Impulsivity or failure to plan ahead.
4. Irritability and aggressiveness, as indicated by repeated physical fights or assaults.
5. Reckless disregard for safety of self or others.
6. Consistent irresponsibility, as indicated by repeated failure to sustain consistent work behavior or honor financial obligations.
7. Lack of remorse, as indicated by being indifferent to or rationalizing having hurt, mistreated, or stolen from another.
Many people with antisocial personality are also very charming and personable, but are also very narcissistic, having a very high opinion of themselves. They tend to have frequent problems with authority, rules and directives, which in turn leads to trouble keeping jobs and maintaining relationships. They are frequently impulsive, giving little thought to the consequences of their actions. Combine this with a tendency to become bored easily, and you can see why many people with this diagnosis end up in the criminal justice system. Men are more likely than women to receive the diagnosis.
There is debate in the mental health field whether psychopathy and sociopathy are appropriately paired under the antisocial heading. Because psychopathy is diagnosed primarily by interpersonal relationships and the individuals affect, where as ASPD is diagnosed by observed social and behavioral deviance, some clinicians feel the two should be separated.
What causes it remains unclear, though the amygdala may play a key role. The amygdala is known to influence fear reactions and the "animal instinct" and behavioral control in humans. Damage done to this portion of the brain tends to show as a decrease in impulse control and patients diagnosed with ASPD frequently show damage to the amygdala.