Definitions of abnormality, including deviation from social norms, failure to function adequately, statistical infrequency and deviation from ideal mental health.

What this dot point is asking

AQA wants you to describe and evaluate the four definitions of abnormality. The exam skill is to define each precisely and to attach the standard strength and limitation to each, since evaluation (often the cultural-relativism point) is what these questions reward.

The four definitions

Each definition captures a different intuition about what "abnormal" means. Statistical infrequency uses the mathematics of the normal distribution: a behaviour or characteristic is abnormal if it lies far from the average, for example an IQ more than two standard deviations below the mean of 100. Deviation from social norms judges behaviour against the unwritten rules a society holds about acceptable conduct; breaking those rules (for example, behaving in a way considered antisocial) is treated as abnormal. Failure to function adequately focuses on whether a person can cope with the ordinary demands of daily life, such as holding down a job, maintaining hygiene and relationships. Deviation from ideal mental health takes the opposite route from the others, first defining what good mental health looks like and then treating departures from it as abnormal.

The two definitions that come with named criteria are the most testable. For failure to function adequately, Rosenhan and Seligman identified signs including personal distress (the person suffers), maladaptive behaviour (behaviour that works against the person's interests), unpredictability, irrationality and observer discomfort. For deviation from ideal mental health, Jahoda's six criteria are a positive self-attitude, self-actualisation, accurate perception of reality, autonomy, resistance to stress, and environmental mastery. Evaluation runs along common themes. Statistical infrequency is objective but cannot distinguish desirable rarity (a genius IQ is just as rare as a very low one) from undesirable rarity, and some disorders are statistically common. Deviation from social norms is useful but is culturally and historically relative (homosexuality was once classed as a disorder) and risks abuse as a tool of social control. Failure to function is practical but relies on subjective judgement about who decides what counts as adequate. Deviation from ideal mental health is positive and holistic but sets such a demanding standard that almost no one meets all six criteria, and the criteria (especially autonomy and self-actualisation) reflect Western individualist values, making it culturally biased. The strongest conclusion is that the definitions are complementary, each capturing part of abnormality, rather than competing.