Defining mental disorder. Exploring the 'natural function' approach

As an important element in the ongoing efforts to develop the DSM-V, researchers have again scrutinised the concept of mental disorder and accentuate that his is both a crucial field and one that needs additional work [1,2]. This is no surprise. The concept of mental disorder is at the foundation of psychiatry. While adequately defining mental disorder is a notoriously thorny issue with far reaching implications for psychiatric research, diagnosis, socio-political interventions, at least since the publication of the DSM-III there has been a consensus of the fact that a convincing definition of mental disorder is required. In addition, for many, the credibility of psychiatry as a medical discipline to a certain extent depends on a convincing definition. On the background of the socio-political developments that the American Psychiatric Association (A.P.A.) faced during the 1970s the effort in the DSM-III and DSM-IV to define mental disorder becomes more transparent [3,4]. First, proponents of the "anti-psychiatry" were radically questioning the scientific legitimacy of psychiatry: Sceptics like Szasz [5] were arguing that psychiatry, rather than being a genuine branch of medicine, is a masked form in which social power is exercised. Simply, the exercise of power works through a medicalisation of 'problems in living' that - following Szasz - are really non-medical in nature. Second, the classification of homosexuality as a mental disorder, as proposed by the DSM-II, became increasingly untenable. Third, support groups have worked for the recognition of mental disorders as a disease like others (diseases of the brain) to lessen stigmatisation and to secure the same benefits to the mentally ill as to the physically ill.Against the background of these issues that psychiatry was struggling with, it is comprehensible that only a value-free definition of mental disorder seemed really acceptable. The idea is that if mental disorder could be defined relying solely on 'pure' f