Dr David Spiegel, chair of psychiatry and behavioural sciences at Stanford University, California, told the conference that monitoring its effects inside the brain had proved it could change perceptions.
Hypnotised volunteers were asked to look at a black and white grid which they were told was filled with colour.
Brain scans that examined blood flow in the part of the brain involved in colour recognition showed changes identical to those to be expected had the volunteers really been looking at colours.
Dr Spiegel said: 'Believing was seeing. The patients were not simply telling us what we wanted to hear.'
Read more: http://www.dailymail.co.uk/health/article-100985/Hypnosis-just-stage-trick.html#ixzz2UuKGvydD
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