Great expectations: “Expectation can be an

effective drug. A placebo

stimulates the brain in the

same way as drug treatment

in Parkinson’s disease,

shows a Canadian study.

Both increase the release of

the brain chemical

dopamine, fuelling recent

controversy over whether the

placebo effect exists at all.

Thought to affect around

30% of patients, the placebo

effect, in which patients

benefit from treatment

because of expectation

alone, is a long-standing

medical conundrum. Drugs

are generally approved on

the basis of their

effectiveness over placebos.” Nature It is unclear to me what is so astounding about this paper, widely blinked as mindboggling. Of course the placebo effect must accomplish the same physiological and biochemical effects as the ‘real’ treatment, to the extent that it works. The mystery is how the mind’s belief mobilizes the physiological reactions, not that it does. Actually, given the intimate relationship between dopamine and cognition, I’m not surprised there is a robust placebo effect in Parkinson’s Disease. Perhaps the question should be turned on its head — how much of the effect of the active treatment too is mobilized by belief? Physicians have always known that the hopeful attitude they bring toward the treatments they propose to their afflicted patients makes a great deal of difference to the outcome.