( dpa ) - A fine line separates a "quirk" from a personality disorder, be it strong mistrust or exaggerated perfectionism.
One criterion is whether the person's perceptual or behavioural patterns result in lasting personal suffering or adverse effects on the people around them, according to the German Society of Psychiatry, Psychotherapy and Neurology (DGPPN).
Pronounced personality traits can be roughly divided into three categories: strange and eccentric, emotional and moody, and insecure and obsessive-compulsive, noted the DGPPN's Professor Martin Bohus.
"People with a paranoidal personality disorder, for example, tend to misinterpret neutral or friendly acts by others as hostile or insulting," he said.
For fear of being taken advantage of, Bohus remarked, affected individuals often harboured unjustified suspicions regarding things like their partner's faithfulness or the fairness of the treatment they received at work.
Bohus explained that an obsessive-compulsive personality disorder, on the other hand, was marked by exaggerated perfectionism in which amusements and interpersonal relationships were neglected.
Since the boundary between normal and abnormal behaviour is fuzzy, not all pronounced personality traits need to be treated, Bohus said. But if a person suffers from such a trait or its consequences, psychotherapeutic treatment is advisable, he added.