BBC Radio 4 has just broadcast the first part of a fantastic two part series on placebo, the most effective evidence-based treatment known to science.
It’s written and presented by Bad Science’s Ben Goldacre and is a wonderful trip through the history and science of what we know about this most psychological of treatments.
One of the most interesting recent placebo findings has been that children show a greater placebo response than adults as demonstrated in a systematic analysis of epilepsy treatment trials.
This matches up with the fact that children and generally more hypnotically suggestible than adults.
Various studies in the 1960s and 70s tracked hypnotisability through childhood and found that susceptibility to suggestion varies as a function of age. This summary is from p120 of the excellent academic book The Highly Hypnotizable Person:
Around the age of 7 children show measurable hypnotic ability, which appear to increase until around the age of 12, where it seems to peak. If then appears to plateau for about two years, decreases moderately during adolescence, and then remains stable during early and middle adulthood.
While both placebo and hypnotisability involve the general concept of ‘suggestion’ it’s not been clear whether they reflect the same things at work.
However, recent work by psychologist Amir Raz has suggesting that both hypnosis and placebo may both work through the manipulation of attention, essentially influencing the focus of processing within the brain to alter how it regulates the body and mind.