Failure to function adequately - Occurs when someone is unable to cope with ordinary demands of day-to-day living
Rosenhan and Seligman (1989) proposed signs that can be used to determine when someone is not coping:
When a person no longer conforms to standard interpersonal rules e.g. respecting personal space
When a person experiences severe personal distress
When a person's behaviour becomes irrational or dangerous for themselves or others
Example: Intellectual disability disorder
Criteria for diagnosis
Having a very low IQ (a statistical infrequency)
AND failing to function adequately
STRENGTH of Failure to function criterion: MEASURABLE
Example: The GAF scale is a method of measuring how well individual's function in everyday life, considers Rosenhan and Seligmans's sections - allows for the extent of the failure to function to be measured
Link: So the decision of whether a behaviour is abnormal or not can be made in a relatively objective way
STRENGTH of Failure to function criterion: Behaviour is OBSERVABLE
Example: Can be seen by others around the individual, eg not getting out of the bed in the morning
Link: So problems can be picked up by others, and can intervene
WEAKNESS of Failure to function criterion: Everydaylife varies
'Normal' everyday life varies within and across cultures
Example: Not having a job/permanent address may seem like failing to function. However, some alternative lifestyles choose to live 'off-grid'
Link: People who make unusual choices are at risk of being labelled as abnormal and their freedom of choice may be restricted