London: Having a good laugh with friends really does help to deal with pain, suggests a new study by an international research team led by Oxford University.
   
The team found that when we laugh properly, as opposed to producing a polite titter, the physical exertion leaves us exhausted and thereby triggers the release of protective endorphins. These endorphins, one of the complex neuropeptide chemicals produced in the brain, manage pain and promote feelings of well being.
   
According to the team's research paper, published online in Proceedings of the Royal Society B, watching just 15 minutes of comedy with others increased the pain threshold by an average of about ten percent, a university release said.
   
The fact that only this type of laughter releases endorphins has probably evolved as a way of promoting socializing amongst humans, says the paper.
   
It points out that many studies have already shown that laughter is 30 times more likely to occur if you are with others than when alone. The endorphin rush appears to be limited to a good belly laugh, shared with others.
   
The research paper makes an important distinction between relaxed, unforced laughter that creases the eyes, and polite laughter which does not reach the eyes, the release added.
   
It concludes that when we laugh properly we produce a series of exhalations without drawing breath, an involuntary physical mechanism that is limited to humans and appears to trigger the release of endorphins.
   
Laughter is important to other great apes too but they breathe in as well as out when they laugh, unlike humans.
   
The paper is based on more than 10 years of research in which different experiments were staged to discover what determined our level of pain tolerance.
   
Subjects were asked to watch TV clips or live staged shows, and their pain thresholds were measured before and after doing this using a number of different pain manipulations (ice-cold sleeves, pressure from a blood pressure cuff, and a painful, strenuous quad work-out).

(Agencies)