Antisocial personality disorder (ASPD), also known as dissocial personality disorder (DPD) and sociopathy, is a personality disorder, characterized by a pervasive pattern of disregard for, or violation of, the rights of others. An impoverished moral sense or conscience is often apparent, as well as a history of crime, legal problems, or impulsive and aggressive behavior. Antisocial personality disorder is the name of the disorder as defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM). Dissocial personality disorder (DPD) is the name of a similar or equivalent concept defined in the International Statistical Classification of Diseases and Related Health Problems (ICD), where it states that the diagnosis includes antisocial personality disorder. Both manuals have similar but not identical criteria for diagnosing the disorder. Both have also stated that their diagnoses have been referred to, or include what is referred to, as psychopathy or sociopathy, but distinctions have been made between the conceptualizations of antisocial personality disorder and psychopathy, with many researchers arguing that psychopathy is a disorder that overlaps with, but is distinguishable from ASPD. Signs and symptoms Antisocial personality disorder is defined by a pervasive and persistent disregard for morals, social norms, and the rights and feelings of others.Individuals with this personality disorder will typically have no compunction in exploiting others in harmful ways for their own gain or pleasure, and frequently manipulate and deceive other people, achieving this through wit and a facade of superficial charm, or through intimidation and violence. They may display arrogance and think lowly and negatively of others, and lack remorse for their harmful actions.Irresponsibility is a core characteristic of this disorder: they can have significant difficulties in maintaining stable employment as well as fulfilling their social and financial obligations, and people with this disorder often lead exploitative, unlawful, or parasitic lifestyles. Those with antisocial personality disorder are often impulsive and reckless, failing to consider or disregarding the consequences of their actions. They may repeatedly disregard and jeopardize their own safety and the safety of others, and place themselves and others in danger. They are often aggressive and hostile and display a disregulated temper, and can lash out violently with provocation or frustration. Individuals are prone to substance abuse and addiction, and the abuse of various psychoactive substances is common in this population. This behavior leads them into frequent conflict with the law, and many people with ASPD have extensive histories of antisocial behavior and criminal infractions stemming back before adulthood. Serious problems with interpersonal relationships are often seen in those with the disorder. Attachments and emotional bonds are weak, and interpersonal relationships often revolve around the manipulation, exploitation and abuse of others. While they generally have no problems in establishing relationships, they may have difficulties in sustaining and maintaining them. Relationships with family members and relatives are often strained due to their behavior and the frequent problems that these individuals may get into. Conduct disorder Main article: Conduct disorder While antisocial personality disorder is a mental disorder diagnosed in adulthood, it has its precedent in childhood. The DSM-5's criteria for ASPD require that the individual have conduct problems, evident by the age of 15. Persistent antisocial behavior as well as a lack of regard for others in childhood and adolescence is known as conduct disorder and is the precursor of ASPD.About 25-40% of youths with conduct disorder will be diagnosed with ASPD in adulthood. Conduct disorder (CD) is a disorder diagnosed in childhood that parallels the characteristics found in ASPD, and is characterized by a repetitive and persistent pattern of behavior in which the basic rights of others or major age-appropriate norms are violated. Children with the disorder often display impulsive and aggressive behavior, may be callous and deceitful, and may repeatedly engage in petty crime such as stealing or vandalism, or get into fights with other children and adults. This behavior is typically persistent and may be difficult to deter with threat or punishment. Attention deficit hyperactivity disorder (ADHD) is common in this population, and children with the disorder may also engage in substance abuse." CD is differentiated from oppositional defiant disorder (ODD) in that children with ODD do not commit aggressive or antisocial acts against other people, animals and property, though many children diagnosed with ODD are subsequently rediagnosed with CD. Two developmental courses for CD have been identified based on the age at which the symptoms become present. The first is known as the "childhood-onset type" and occurs when conduct disorder symptoms are present before the age of 10 years. This course is often linked to a more persistent life course and more pervasive behaviors, and children in this group have greater levels of ADHD symptoms, neuropsychological deficits, more academic problems, increased family dysfunction, and higher likelihood of aggression and violence. The second is known as the "adolescent-onset type" and occurs when conduct disorder develops after the age of 10 years. Compared to the childhood-onset type, less impairment in various cognitive and emotional functions are present, and the adolescent-onset may remit by adulthood. In addition to this differentiation, the DSM-5 provides a specifier for a callous and unemotional interpersonal style, which reflects characteristics seen in psychopathy and are believed to be a childhood precursor to this disorder. Compared to the adolescent-onset subtype, the childhood onset subtype, especially if callous and unemotional traits are present, tend to have a worse treatment outcome. Causes and pathophysiology Personality disorders are seen to be caused by a combination and interaction of genetic and environmental influences. Genetically, it is the intrinsic temperamental tendencies as determined by their genetically influenced physiology, and environmentally, it is the social and cultural experiences of a person in childhood and adolescence encompassing their family dynamics, peer influences, and social values. Genetic Research into genetic associations in antisocial personality disorder is suggestive that ASPD has some or even a strong genetic basis. Prevalence of ASPD is higher in people related to someone afflicted by the disorder. Twin studies, which are designed to discern between genetic and environmental effects have reported significant genetic influences on antisocial behavior and conduct disorder, In the specific genes that may be involved, one gene that has seen particular interest in its correlation with antisocial behavior is the gene that encodes for Monoamine oxidase A (MAO-A), an enzyme that breaks down monomamine neurotransmitters such as serotonin and norephinephrine. Various studies examining the gene's relationship to behavior have suggested that variants of the gene that results in less MAO-A being produced, such as the 2R and 3R alleles of the promoter region have associations with aggressive behavior. The association is also found influenced by negative experience in early life, with children possessing a low-activity variant (MAOA-L) with who experienced such maltreatment being more likely to develop antisocial behavior than those with the high-activity variants (MAOA-H). Even when environmental interactions (e.g. emotional abuse) are controlled for, a small association between MAOA-L and aggressive and antisocial behavior remains. The gene that encodes for the serotonin transporter (SCL6A4), a gene that is heavily researched for its associations with other mental disorders, is another gene of interest in antisocial behavior and personality traits. Genetic associations studies have suggested that the short "S" allele is associated with impulsive antisocial behavior and ASPD in the inmate population.However, research into psychopathy find that the long "L" allele is associated with the Factor 1 traits of psychopathy, which describes its core affective (e.g. lack of empathy, fearlessness) and interpersonal (e.g. grandiosity, manipulativeness) personality disturbances. This is suggestive of two different forms, one associated more with impulsive behavior and emotional dysregulation, and the other with predatory aggression and affective disturbance, of the disorder. Various other gene candidates for ASPD have been identified by a genome-wide association study published in 2016. Several of these gene candidates are shared with attention-deficit hyperactivity disorder, which ASPD is comorbid with. Physiological Hormones and neurotransmitters Traumatic events can lead to a disruption of the standard development of the central nervous system, which can generate a release of hormones that can change normal patterns of development.Aggressiveness and impulsivity are among the possible symptoms of ASPD. Testosterone is a hormone that plays an important role in aggressiveness in the brain.For instance, criminals who have committed violent crimes tend to have higher levels of testosterone than the average person. The effect of testosterone is counteracted by cortisol which facilitates the cognitive control on impulsive tendencies. One of the neurotransmitters that have been discussed in individuals with ASPD is serotonin, also known as 5HT. A meta-analysis of 20 studies found significantly lower 5-HIAA levels (indicating lower serotonin levels), especially in those who are younger than 30 years of age. J.F.W. Deakin of University of Manchester's Neuroscience and Psychiatry Unit has discussed additional evidence of a connection between 5HT (serotonin) and ASPD. Deakin suggests that low cerebrospinal fluid concentrations of 5-HIAA, and hormone responses to 5HT, have displayed that the two main ascending 5HT pathways mediate adaptive responses to post and current conditions. He states that impairments in the posterior 5HT cells can lead to low mood functioning, as seen in patients with ASPD. It is important to note that the dysregulated serotonergic function may not be the sole feature that leads to ASPD but it is an aspect of a multifaceted relationship between biological and psychosocial factors. While it has been shown that lower levels of serotonin may be associated with ASPD, there has also been evidence that decreased serotonin function is highly correlated with impulsiveness and aggression across a number of different experimental paradigms. Impulsivity is not only linked with irregularities in 5HT metabolism but may be the most essential psychopathological aspect linked with such dysfunction. Correspondingly, the DSM classifies "impulsivity or failure to plan ahead" and "irritability and aggressiveness" as two of seven sub-criteria in category A of the diagnostic criteria of ASPD. Some studies have found a relationship between monoamine oxidase A and antisocial behavior, including conduct disorder and symptoms of adult ASPD, in maltreated children.