definitions of abnormality

• statistical infrequency

  behaviour is considered abnormal if it is statistically rare. e.g., 65% of people have an IQ of 85-115, IQ much lower than 85 or much higher than 115 would be abnormal.
• when is behaviour considered statistically rare

  when it is outside of the 'normal distribution' (usually 5%)
• deviation from social norms

  behaviour is considered abnormal if it deviates from 'unwritten' rules in society, it could also be behaviour which makes other people nervous. e.g., antisocial personality disorder: impulsive, pleasing only themselves.
• deviation from ideal mental health

  behaviour is considered abnormal if it deviates from the six critera suggested by Marie Jahoda in 1958.
• what are the six criteria suggested by Marie Jahoda

  autonomy, self-actualisation, positive attitudes towards self, accurate perception of reality, mastery of the environment and resistance to stress
• autonomy

  individuals should be independent and self-reliant
• self-actualisation

  individuals should focus on the future and their self growth
• positive attitudes towards self

  individuals should have high self-esteem and a strong sense of identity
• accurate perception of reality

  individuals should have a truthful and realistic view of the world
• mastery of the environment

  individuals should have the ability to love, function at work and interpersonal relationships, adjust to new situations and solve problems.
• resistance to stress

  individuals should have effective coping mechanisms to deal with stress.
• failure to function adequately

  behaviour is considered abnormal when it affects a persons everyday life, it may disrupt their ability to work or have relationships. E.g., maladaptive behaviour.