Thrilling concerts often leave heavy metal fans with headaches, but a sham medicine may be all that is needed to ease their pains.

Well, this suggestion is based on a study by McGill University researchers Montreal, Canada, which has shown that thrill-seekers enjoy a stronger placebo response than people with more restrained personalities.

Neuroscientist Petra Schweinhardt has revealed that this conclusion was arrived at after testing 22 male university students.

She agrees that it is too early to prescribe phoney pain treatments based on personality tests.

The researcher, however, insists should larger trials confirm her team's findings, they may help pharmaceutical companies avoid testing experimental drugs on people with strong placebo responses.

During the study, Petra and her colleagues injected a pain-inducing saline solution into the left and right legs of willing volunteers for 20 minutes.

"It's a dull pain, a dumb pain, it's aching, it's annoying," New Scientists quoted her as saying.

She revealed that before the study started, all participants were told that the research team were testing an experimental analgesic cream - really just skin lotion.

With a view to making the rouse more believable, the researchers said that they would test one leg with the treatment and one leg with a non-medicated lotion.

"We really told them the whole story in order to counteract any doubts in the treatment," Schweinhardt says.

The researchers asked the participants to rate their pain across both trials, and observed that the difference amounted to the placebo response.