There is mounting evidence that hypnosis is both a psychological and a neurophysiological phenomenon:
- Electroencephalograph (EEG) studies have shown that for highly hypnotizable subjects, a hypnotic induction procedure produces reliable alterations in brain activity that are associated with responsiveness to suggestions.
- Positron emission tomography (PET) studies have shown that when highly hypnotizable subjects respond to a suggestion to add color to black-and-white image, their subjective experience was reliably associated with changes in brain activity in areas of the brain that process information about color.
- Functional magnetic resonance imaging (fMRI) studies have shown that, in trance, context-specific suggestions can differentially modulate activity in specific brain sites.
The Neuroscience of Hypnosis (John E. Alexander PhD et.al., American Society of Clinical Hypnosis, 2017)