Rep36 Understanding Personality Disorder

2.2.5 Conclusions
It is difficult to determine whether biological,
psychological or social causes are predominant
in any individual case or to discriminate between
these factors. However, it is apparent that no
single factor within an individual’s environment,
even in combination with a biological
vulnerability, would be likely to produce a
significant level of personality disorder.
Therefore, multiple adverse life experiences are
likely to be necessary.
Social rules determine which behaviours
society considers disordered. These rules are
important during the identifying of certain
behaviours, thoughts and emotional responses as
unacceptable and serve to shape the responses of
individuals to meet the needs of their society.
This would indicate that there is a link between
cultural norms and the threshold for diagnosing
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Can personality change?
Personality traits appear to be stable from around the age of 30 years. This has led some people to
conclude that resistance to change is a fundamental attribute of personality and that the
possibilities for changing adult personality are limited (Costa & McCrae, 1994). However, less is
known about the stability of personality processes underlying traits, and goals or motives may be
more subject to change across the life span. For example, our priorities or ‘personal projects’
change at different stages of life. 
There have been few studies exploring whether the symptoms of personality disorder change
over time, but it is generally assumed that because the definition of personality disorder refers to
‘enduring patterns’, this therefore implies temporal continuity. Research studies have, however,
found that some of the problems associated with borderline and antisocial personality disorders
reduce steadily over time, even without treatment (Moran, 1999; Stone, 1993; Zanarini 
et al
.,
2003). This improvement in functioning may be due to people tending to become less impulsive
as they get older (Harpur & Hare, 1994). Whether personality can be changed by clinical
intervention, and what aspects of personality might be amenable to change, therefore remain
significant questions to be answered by research.