Personality traits contribute to 'placebo effect'

Apr 23, 2009

(PhysOrg.com) -- Researchers at McGill University have found for the first time that novelty seeking personality types enjoy a stronger “placebo response,” or pain relief caused by the administration of a sham treatment, than people with reserved personalities. The study hypothesizes that the anticipation of pain relief, in this case triggered by the administration of a placebo, is a special case of reward anticipation. Since dopamine is a key neurotransmitter in reward processing, personality traits linked to dopamine, such as novelty seeking, were studied.

Their study is published in the current issue of The Journal of Neuroscience.

Petra Schweinhardt, a researcher at the Alan Edwards Centre for Research on Pain, McGill Faculty of Dentistry, and Faculty of Medicine, (Neurology and Neurosurgery), and colleagues tested a group of 22 healthy males, injecting them with a pain-inducing saline solution into their left and right legs for twenty minutes. Prior to testing, participants were told that the research team was testing an experimental analgesic cream, which was really just skin lotion. The researchers then told participants that they would test one leg with the treatment and one leg with a non-medicated lotion.

The researchers asked the participants to rate their pain across both trials, and the difference amounted to the response. Not everyone reported from the placebo, but those who did scored higher on tests that gauged novelty-seeking personalities.

The other component of the research looked at the ventral striatum, an important brain region for the processing of reward. An MRI was taken of all subjects and a three-way relationship was found between the placebo response, the and the amounts of gray matter in this particular brain region.

“Our study links clearly these personality traits with the placebo analgesic effect. It will potentially help us one day to exploit the clinically - more than we are doing today,” says Schweinhardt. “The more knowledge we have about the placebo effect, the more it will be accepted - this is important, because we know that it is a true physiological phenomenon. My aim is to raise the acceptance of the placebo effect as a therapeutic tool”.

Provided by McGill University (news : web)

Explore further: Cannabis-based medicine to be tested as child epilepsy therapy

add to favorites email to friend print save as pdf

Related Stories

Brain region central to placebo effect identified

Jul 18, 2007

Researchers have pinpointed a brain region central to the machinery of the placebo effect—the often controversial phenomenon in which a person’s belief in the efficacy of a treatment such as a painkilling drug influences ...

The 'placebo effect' is studied

Nov 22, 2005

University of Michigan researchers say they are investigating the "placebo effect," in which pills with no medicinal value work in some people.

Pain relief effectiveness down to mind-set?

Dec 21, 2006

Research by the Human Pain Research Group at The University of Manchester suggests that people's responses to placebo or 'dummy' pain relief varies according to their way of thinking.

Study evaluates placebo effectiveness

Feb 01, 2006

Harvard Medical School scientists who usually use placebos to test a new treatment's effectiveness have conducted a trial testing placebos.

Recommended for you

'Microlesions' in epilepsy discovered by novel technique

Dec 16, 2014

Using an innovative technique combining genetic analysis and mathematical modeling with some basic sleuthing, researchers have identified previously undescribed microlesions in brain tissue from epileptic ...

Thumbs-up for mind-controlled robotic arm (w/ Video)

Dec 16, 2014

A paralysed woman who controlled a robotic arm using just her thoughts has taken another step towards restoring her natural movements by controlling the arm with a range of complex hand movements.

The sense of smell uses fast dynamics to encode odors

Dec 16, 2014

Neuroscientists from the John B. Pierce Laboratory and Yale School of Medicine have discovered that mice can detect minute differences in the temporal dynamics of the olfactory system, according to research ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.