The scientific studies of mental illness and antisocial behavior continue to occupy largely separate intellectual domains. Although some patterns of persistent antisocial behavior are nominally accorded diagnostic labels such as Antisocial Personality Disorder or Conduct Disorder, the default approach to individuals who engage in persistent antisocial behavior is to view their patterns of behavior through a moral lens (as "badness") rather than through a mental health lens (as "madness").
In some senses this distinction represents progress. As recently as the 19th and early 20th century, individuals affected by all manner of psychopathologies were routinely confined and in some cases punished or even executed. Along with the emergence of the understanding that symptoms of mental illness reflect disease processes, the emphasis has shifted toward a focus on prevention and treatment. However, this shift has not applied equally to all forms of psychopathology. For example, disorders primarily characterized by internalizing symptoms (persistent distress or fear, self-injuring behaviors) versus externalizing symptoms (persistent anger or hostility, antisocial and aggressive behaviors) are strikingly similar in many respects: comparable prevalence; parallel etiologies and risk factors; and similarly detrimental effects on social, educational, and vocational outcomes. But whereas immense scientific resources are aimed at identifying the causes and disease processes of internalizing symptoms and developing therapies for them, the emphasis for externalizing symptoms remains primarily on confinement and punishment, with relatively few resources devoted to identifying causes and disease processes or developing therapies. Comparisons of federal mental health funding, clinical trials, available therapeutic agents, and publications in biomedical journals directed toward internalizing versus externalizing symptoms all confirm this pattern. It is likely that this asymmetry results from multiple forces, including cognitive and cultural biases that influence decision-making processes among scientists and policymakers alike and ultimately erode support for the study of antisociality as a form of mental illness.
Cognitive biases include widespread tendencies to view actions that cause harm to others as fundamentally more intentional and blameworthy than identical actions that happen not to result in harm to others, as has been shown by Joshua Knobe and others in investigations of the "side-effect effect", and to view agents who cause harm as fundamentally more capable of intentional and goal-directed behavior than those who incur harm, as has been shown by Kurt Gray and others in investigations of distinction between moral agents and moral patients. These biases dictate that an individual who is predisposed to behavior that harms others as a result of genetic and environmental risk factors will be inherently viewed as more responsible for his or her behaviors than another individual predisposed to behavior that harms himself as a result of similar genetic and environmental risk factors. The tendency to view those who harm others as responsible for their actions, and thus blameworthy, may reflect seemingly evolved tendencies to reinforce social norms by blaming and punishing wrongdoers for their misbehavior.
Related to these cognitive biases are cultural biases that dictate self-interested behavior to be normative. Individualistic cultures view self-interest as humans' cardinal motive—the motive that supersedes all other motives and that ultimately underlies all human behavior. This norm may reflect the dominance of rational choice theories of human behavior favored in economics and which have many adherents among scholars in other academic domains, including psychologists, biologists, and philosophers. Belief in the norm of self-interest is widespread among the lay public as well. The norm of self-interest renders behavior that is not self-interested inherently non-normative—or "abnormal." This may explain the tendency to view behaviors and patterns of thinking that cause oneself harm or distress as clearly reflecting irrationality and mental illness whereas otherwise similar behaviors and patterns of thinking that cause others harm or distress are viewed as reflecting rational, if immoral, choices. Indeed, if the harm to others is in the service of achieving benefit for the self, such behaviors may even be seen as hyper-rational.
The United States is an unusually individualistic country, which may help to explain its unusually strong adherence to the norm of self-interest, and also perhaps its unusually punitive (rather than treatment-focused) approach to crime and aggression. This approach can be contrasted with that of, for example, the relatively less individualistic Scandinavian nations where treatment rather than punishment of even serious criminal offenders is emphasized. Mental health-focused approaches may reduce recidivism, further supporting the possibility that externalizing behaviors, including crime and aggression, may be most effectively considered symptoms of psychopathology in need of treatment rather than simple failures of impulse control in need of punishment—that the distinction between antisociality and mental illness should be abandoned.