Antisocial Personality Disorder (apd) and The Impact Nature Have on It

Abstract

The etiology of Antisocial Personality Disorder (APD) is correlated to a myriad of factors without definite certainty as to which is prevalent. This study was conducted to prove that both nature and nurture are, combined, responsible for the etiology of APD. Samples were taken primarily from Willem Martens (2000) and Jonathan Kellerman (1999). The methods of which they obtained their information are adoption, particularly of twins, statistics, and previously conducted studies. Each factor linked to possible causation was analyzed in this study: (1) genetic, (2) biological, (3) environmental and (4) psychological. The conclusion reached was that further research is needed to explain where nature and nurture factors begin and end in the development of APD.

The Etiology of Antisocial Personality Disorder

Commonly known as psychopathy or sociopathy, Antisocial Personality Disorder (APD) is a disorder defined by the Diagnostic and Statistical Manuel (DSM-5) as “-a pervasive pattern of disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood” (American Psychology Association, 2013). It possesses a completely different connotation than the dictionary definition of antisocial. Rather than introverted, an individual diagnosed with APD, displays erratic behavior (e.g. impulsive, violent, or criminal). Other traits or diagnostic signs include pathological lying, recklessness, irresponsibility, and a lack of empathy (Schacter, 2013). In order to be diagnosed, a person must meet these and other required criterion listed in the DSM-5. Adults who are diagnosed with the disorder are repeatedly described as uncaring, emotionless, manipulative, or cruel because of their remorselessness in harming others, whether physically, emotionally, or economically. Approximately 3.6% of the population has APD, as taken from Grant et al. (Schacter, 2013). But what causes such a personality disorder to form? Is it genetic, the environment, or specific biological/psychological factors? According to one study, “Although the interpersonal-affective and antisocial facets of psychopathy have received extensive empirical investigation, there is a lack of concomitant research exploring their genetic and environmental underpinnings” (Blonigen, 2005). Psychologists have searched for the answer by examining children, particularly adolescent males, who display early conduct disorder behavior and criminals already diagnosed with APD. However, there is no consensus on one, single factor leading to the direct causation of APD. The goal of this paper is to show, rather, that both nature and nurture play a role in the causation of the disorder.

Literature Review

While no single, genetic predictor has been verified yet, case studies do show that genetic factors influence, albeit indirectly, the likelihood of developing APD. Children of psychopaths, or first-degree biological relatives, are hence more at risk than the general populace (DSM-5, 2005, Martens, 2000). It is common to find these children following in the footsteps of their unstable fathers or mothers. Genetic theorists argue that such children inherit the maladaptive traits of the parent, whether those traits are interpersonal or impulsive (Kellerman, 1999). Conduct behavior problems can still be exhibited even without the presence of the psychopathic parent in the home (Martens, 2000). Other genetic factors include a predisposition to trauma and substance abuse. Willem Martens (2000) theorized in an article he wrote that substance abuse users are an at-risk group because they share the same genetic traits as those diagnosed with APD. Jonathan Kellerman adds to this insight concerning drugs and antisocial individuals: “In fact, drugs play a role on both ends-as cause and effect-for in addition to satisfying pleasure drives, psychoactive chemicals lower inhibition, facilitating risky, reckless, sometimes psychopathic behavior” (1999). Furthermore, substance abuse disorder and APD have a long history of comorbidity. Other personality disorders, schizophrenia in particular, serve as negative predictors of APD (Martens, 2000).

A significant amount of data exists that connect biological factors to the causation of APD. One such factor is the correlation of negative effects on prenatal development to APD. Grete L. Bibring studied the psychology of pregnancy and observed that, “-one became increasingly aware of the high percentage of different forms of pathology in children which were associated to disturbances in their mother” (1959). Malnutrition during the earliest stages of development during a child’s life can affect not only its physical health, but its mental health. Insufficient nutrition as such increases the risk of developing personality disorders, especially APD (Schacter, 2013). Teratogens, such as alcohol and drugs, can cause brain damage and learning disabilities, which in turn, also become precursors of personality disorders. Kellerman lists additional facets, including “-birth complications, prematurity, and postnatal damage” (1999).

Studies of brain structure abnormalities and injuries show stark differentiation between normal and antisocial individuals. These deficits are measured by EEG (electroencephalogram), or brain wave patterns. The areas of the brain which are observed are the frontal lobe (lesions) and the amygdala. When tested for emotional reactivity, criminals with antisocial diagnostic traits displayed little, to no, activity in the frontal areas and high activity in the occipital lobe. This same reaction to both neutral and emotional stimuli suggest that the disorder is a result of a deficit in the frontal lobe. It would explain the disinhibition that those diagnosed with APD display, along with other traits, such as the inability to see right from wrong (i.e. social norms, laws). The results of damage to the brain range from attention deficit, conduct disorder behavior, and low IQ (Kellerman, 1999). Cranial injury can be obtained from trauma to the head, as attributed to child abuse (Kellerman, 1999). However, this study is not entirely comprehensive and needs further research.

Biochemical abnormalities also account for causation of APD, or at least certain traits of it. Low levels of monoamine oxidase (MAO) and serotine (5-HT) are correlated with sensation-seeking tendencies prevalent in antisocial persons (Marten, 2000). High levels of hormones, such as testosterone, T3, and T4, as measured by Psychopathy Checklist-Revised, are also linked to behaviors specific of APD, such as sex and aggression. In the author’s opinion, more research is needed on how chemical and hormonal imbalances create pathological under-arousal.

Besides genetics and biological factors, one must consider the influence of environmental and psychological factors. Aspects of environmental factors that associate with the causation of APD are social factors, such as poverty, educational failure, an abusive or neglectful household, poor peer relations, and class. These are the origins of stress which can correlate with APD behavior, however, they, in themselves, are not predictors (Kellerman, 1999). With that being said, the most influential environment is the home. Parental discord, often resulting in divorce, criminality, disorders in family members, especially the mother, and foster care placement all have negative effects on the mental well-being of at-risk children (Martens, 2000). According to McBurnett, “Poor parent-child relations were associated with aggressive and covert conduct disorders, and socioeconomic status was associated exclusively with aggressive conduct disorders in one study” (Martens, 2000). Depending on the severity of the state of this environment, and other genetic factors, the chances of developing APD during adolescence relatively increase. Conversely, 50% of children with conduct problems raised in such environments do not continue to develop or exhibit them into adulthood (Hill, 2003).

Psychological factors are next to be considered. Two notable factors are impairment of parent-child attachment and emotional deprivation in the preoperational stage of cognitive development, around the first three years of life (Schacter, 2013). Parent-child attachment is the point at which an infant bonds with is caretaker(s) and interpersonal relationships are formed. Infants also begin to display empathy and develop strategies to cope and regulate emotions. When a parent or caregiver neglects or rejects its child’s attempt to develop normally, the child will grow up with an abnormal, technically incomplete, emotional system (Kellerman, 1999). This explanation satisfies why antisocial individuals lack empathy and possess an unrepairable egocentrism. Also, such deprived children are tested to have lower heart rates, similarity to those diagnosed with APD, when prompted to react to stimuli (Kellerman, 1999).

Conclusion

In conclusion, it seems that both nature (genetics, biological) and nurture (environmental, psychological) are responsible for the etiology of APD. It is a variation of both factors dependent on circumstances not entirely within psychologists’ understanding. The insight that can be taken from this study is that a combination of genetic, biological, psychological, and environmental factors lead to the highest probability of APD development. Those most at-risk are children in the early stages of development who are genetically predisposed, have a brain structure abnormality or chemical imbalance, and are raised in an uncaring environment. As for adolescents and adults, substance abuse or brain trauma can also lead to the development of APD without prior meeting of all diagnostic criteria. In the author’s opinion, it raises questions that ultimately lead to further research, especially in the case of biochemical and environment factors. However, the author believes that psychologists are drawing closer to understanding the process of APD’s causation and development.