Mental health articles

Abnormal behaviour has been defined using five different sets of criteria:

•statistical criteria define it as deviation from the average

•deviation-from-the-norm criteria define it as deviation from expected ways of behaving

•mental health criteria define it as the absence of socially desirable characteristics and behaviours (Jahoda 1958)

•social/psychological criteria define it by the presence of undesirable behaviours (Rosenhan and Seligman 1984)

•mental illness criteria define it by the presence of clusters of symptoms

This last approach is the most commonly used, and will be discussed further here. The clusters of behavioural symptoms identified are thought to indicate the presence of an underlying mental illness which may respond to treatment. For example, the most commonly used classification system at the moment is DSM IV, which defines mental disorder as: a clinically significant behaviour or psychological syndrome or pattern that occurs in a person and that is associated with present distress (a painful symptom), disability (impairment of one or more important areas of functioning), a significantly increased risk of suffering death, pain, disability, or an important loss of reedom.

To give an example, clinical depression would be defined by experiencing a low mood for at least two weeks, plus at least five of the following symptoms: change in appetite or weight; changes in sleep patterns; loss of energy; agitation or slowing down; loss of pleasure; guilt feelings; loss of concentration; suicidal thoughts. This system has its faults—for example, the assumption of a physical illness underlying the problem behaviours has been questioned, as has the reliability of the classification system. In practice, an eclectic approach that draws on a range of the criteria mentioned may well be the best compromise.

Tags: abnormal behaviour, Criteria, defining