In 1993, American psychologist Terrie Moffitt described a dual taxonomy of offending behavior in an attempt to explain the developmental processes that lead to the distinctive shape of the age crime curve. Moffitt proposed that there are two main types of antisocial offenders in society: The adolescence-limited offenders, who exhibit antisocial behavior only during adolescence, and the life-course-persistent offenders, who begin to behave antisocially early in childhood and continue this behavior into adulthood. This theory is used with respect to antisocial behavior instead of crime due to the differing definitions of 'crime' among cultures. Due to similar characteristics and trajectories, this theory can be applied to both females and males. Antisocial Personality Disorder Antisocial personality disorder (ASPD) is recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). It is a disorder characterized by a severe disregard for the rights of others. In most of the studies described below, individuals who exhibit antisocial behavior, but have not been diagnosed with ASPD, are used as subjects. Age and Antisocial Personality Disorder The number of arrests spikes in adolescence, but subsequently declines. This spike leads people to wonder whether more offenders are appearing or more offenses are committed by the same few offenders. Evidence shows that there is an increase in both. The most persistent 5% of offenders are responsible for more than 50% of known crimes committed. Several experiments have been conducted to investigate the relationship between extremity and stability of offenses. In one such experiment a group of third grade boys was studied. Out of the most aggressive 5%, 39% of them scored above the 95th percentile on aggression ten years later, and 100% of them were above the median. Aggression and antisocial behavior in a child is a predictor of adult antisocial behavior. Some 'difficult' children exhibit behavioral problems due to neurological dysfunctions. One study looked specifically at neurological damage and infant behavior in 66 low-birth-weight infants from intact middle-class families. These children exhibited traits such as immaturity, overactivity, temper tantrums, poor attention, and poor school performance. Each of the previous traits listed has been linked to antisocial behavior later in life. However, these children were not followed up with later in life to ensure their trajectory into crime. Continuity and Stability of Antisocial Behavior The continuity and stability of antisocial behavior lies at the root of Moffitt's theory. The Adolescent Limited offenders exhibit antisocial behavior without stability