definitions of abnormality

• Deviation from social norms is when a person is considered abnormal if their behaviour doesn't follow social norms.
• All societies have norms and behaviour that is not in line with these norms and values may reflect an illness.
• A strength of deviation from social norms is that it considers how our behaviour affects other people. Classifying people as abnormal under deviation from social norms means we can treat people and prevent them from causing harm to others. This is positive as we can minimise harm to others.
• A limitation of deviation from social norms is that social norms aren't fixed. Social norms change over time and between cultures. For example, homosexuality was considered a mental disorder until 1973 but is now normal and accepted. This is a limitation as what is classed as a mental disorder will also change over time, making the definition subject to constant change and unreliable.
• A limitation of deviation from social norms is that norms vary between cultures. For example, hallucinations are seen to be normal in some cultures, such as Haiti, but in the UK it would indicate schizophrenia. Pinto and Jones 2008 found those of Afro-Caribbean origin are 9x more likely to receive a diagnosis than white British people. This is problematic as what is considered abnormality in one culture, may be considered normal in another.
• Social norms are unwritten rules for how members of a social group are expected to behave. 
• Deviation from ideal mental health considers a person is abnormal if they fail to display behaviours that indicate ideal mental health.
• the more a person deviates from ideal mental health, the more abnormal they are.
• Jahoda 1958 suggested to have good mental health, we must meet 6 criteria:

  • positive self-attitude
  • behaving independently
  • self-actualisation - constantly trying to develop and improve
  • resistance to stress
  • accurate perception of reality
  • environmental mastery
• One strength of the deviation from ideal mental health definition of abnormality is that, by using Jahoda’s criteria, it enables patients who are diagnosed as abnormal to set themselves clear goals for achieving ideal mental health. However, a limitation is that the criteria for ideal mental health are overly demanding. Jahoda's criteria set an unrealistically high standard for mental health that very few meet.
• A limitation of deviation from ideal mental health is culture bias. This definition is based on Western ideals which may not be the same in non-western cultures, such as the concept of self-actualisation. This is problematic as it is difficult to apply the concept of ideal mental health from one culture to another.
• Failure to function adequately considers a person abnormal if they are unable to cope with everyday life.
• A strength of failure to function adequately suggests people who are abnormal are easily identifiable and diagnosed. The behaviours that indicate that a person isn’t coping with everyday life are easy to observe and measure. This is positive as it makes it easy to help identify and treat abnormalities.
• A limitation of failure to function adequately is that abnormality is not always accompanied by dysfunction. The definition fails to identify people who do cope well with everyday life, but that have a mental disorder. For example, Harold Shipman seemed to be coping with everyday life yet he murdered many people. This is problematic as someone in need of treatment could go unnoticed.
• Sue et al argued a normal person should be able to have good personal hygiene, feed themselves adequately, adapt to change, carry out everyday activities and form and maintain social relationships
• Rosenhan & Seligman 1989 identified 4 indicators someone is failing to function:

  • experiencing severe personal distress
  • no longer conforming to standard interpersonal rules such as maintaining personal space.
  • behaviour becomes irrational or dangerous to themselves or others
• A limitation of failure to function adequately is that it is subjective. Interpretation relies on a medical expert as context is important when deciding whether someone is functioning adequately. For example, what may seem irrational in one context may be rational in another such as extreme distress being acceptable if a loved one has died but does not represent abnormality. This is problematic as it limits the definition.
• Statistical infrequency considers behaviour abnormal if it is statistically rare. Behaviour is only considered abnormal if only a small percentage of people display the behaviour.
• Doctors use normal distributions to determine whether a trait is statistically infrequent. A cut-off point of 5%​ is usually used to determine abnormality. When behaviour or trait is shared by 5% of the population or less, it is defined as abnormal.
• A strength of statistical infrequency is that it provides an easy, practical way of diagnosing people. Doctors use normal distribution to determine if a trait is statistically infrequent. This is positive as it is quick and efficient. However, a limitation is determining the cut-off point. The cut-off point will be subjective and each expert will have a different cut-off point. For example, if the cut-off point if 5%, what about the 5.1%. This is problematic as abnormality can be difficult to define and there is no way of deciding where normal behaviour ends and abnormal behaviour begins.
• A limitation of statistical infrequency is that it doesn't account for desirable behaviours. This definition doesn't consider how unusual characteristics may be positive such as high IQ scores, which are uncommon but not seen as a negative quality. This is problematic as it is not a comprehensive definition of abnormality.