Antisocial personality disorder, like other personality disorders, is a longstanding pattern of behavior and experience that impairs functioning and causes distress.
By definition, people with antisocial personality disorder don't follow society's norms, are deceitful and intimidating in relationships, and are inconsiderate of the rights of others. People with this type of personality may take part in criminal activity, but if they do, they are not sorry for their hurtful deeds. They can be impulsive, reckless and sometimes violent. This disorder is far more common and more apparent in men than women.
People with antisocial personality disorder generally do not value "playing by the rules" -- they do so only if they are threatened with punishment. This attitude leads to a tendency to exploit others. They take advantage of the fairness or softheartedness of others, and they feel indifferent toward or even contemptuous of their victims. A person with this disorder has little, if any, ability to be intimate with another person. Any lasting relationships are likely to involve some degree of abuse or neglect. Yet people with this disorder are sometimes charming and can be good actors who use lies and distortion to keep relationships going. Some with antisocial personality disorder have no goal beyond the pleasure of deceiving or harming others.
People with antisocial personality disorder appear to care for no one but themselves. They may be able to understand the emotions of others, but they don't suffer any shame or guilt about the pain they may be causing. Instead, they use their knowledge of others' weaknesses to gain favors or to manipulate an outcome. A person with this disorder usually does not take responsibility for any of his or her own suffering. He or she will blame others when things go badly. Many with this disorder do suffer, because they can be self-defeating, and never get to enjoy the many pleasures that come to people who are better able to have mutual and satisfying relationships.
People with this personality disorder can also have problems such as chronic boredom or irritability, psychosomatic symptoms, pathological gambling, alcohol and substance abuse, and a variety of mood or anxiety disorders. They have a higher risk of suicide. A significant number have had behavior problems or attention deficit disorder as children.
Antisocial personality disorder is probably caused by a combination of factors. Having any of these characteristics does not necessarily mean that a person has antisocial personality disorder.
Influences from the environment. A chaotic family life contributes to the development of this personality disorder, especially where there has been little supervision from parents or other adult role models. The disorder also may be more common where the community is not supportive or provides little reward for positive behavior. In some situations, there may even be reinforcement for sociopathic behavior.
Genetic (inherited) or biological factors. Researchers have found certain physiological responses that may occur more frequently in people with antisocial personality disorder. For example, they have a comparatively flat response to stress. They seem to get less anxious than the average person. They seem to have a harder time maintaining daytime arousal. They also have a weak "startle reflex," the involuntary response to loud noises. This relative insensitivity may affect their ability to learn from reward and punishment.
The frontal lobe, the area of the brain that governs judgment and planning, also appears to be different in people with antisocial personality disorder. Some researchers have found changes in the volume of brain structures that mediate violent behavior. People with this kind of brain function may thus have more difficulty restraining their impulses, which may account for the tendency toward more aggressive behavior. Neurobiologists cannot say with certainty that these variations in brain structure are a cause of antisocial personality. The variations could easily be the result of life experiences that are more common in people with this personality disorder rather than a cause.