Researchers in Britain say they have confirmed what many already suspected - that comedians are a little bit mad.
They score highly on characteristics that in extreme cases are associated with mental illness, a study suggests.
There has been little research on whether comedians have some of the traits - in a healthy form - associated with psychosis, the BBC reports.
The research team from the University of Oxford and Berkshire Healthcare NHS Foundation Trust studied 523 comedians (404 men and 119 women) from the UK, US and Australia.
They looked at aspects such as belief in telepathy and paranormal events, distractibility and difficulty in focusing thoughts, reduced ability to feel social and physical pleasure and impulsive non-conformity.
The questionnaire was also completed by actors and by a group of people who worked in non-creative areas.
The researchers found comedians scored significantly higher on all four types of psychotic personality traits than the general group, with particularly high scores for both extroverted and introverted personality traits.
The researchers believe this unusual personality structure may help explain the ability of comedians to entertain.