Hypnosis works by modulating activity in brain regions associated with focused attention, and this study offers new details regarding neural capacity for hypnosis.
"Our results provide novel evidence that altered functional connectivity in [the dorsolateral prefrontal cortex] and [the dorsal anterior cingulate cortex] may underlie hypnotizability," the researchers wrote in their paper.
For the study, Spiegel and his Stanford colleagues performed functional and structural MRI scans of the brains of 12 adults with high hypnotizability and 12 adults with low hypnotizability.
The researchers looked at the activity of three different networks in the brain: the default-mode network, used when one's brain is idle; the executive-control network, which is involved in making decisions; and the salience network, which is involved in deciding something is more important than something else.
The findings, Spiegel said, were clear: Both groups had an active default-mode network, but highly hypnotizable participants showed greater co-activation between components of the executive-control network and the salience network. More specifically, in the brains of the highly hypnotizable group the left dorsolateral prefrontal cortex, an executive-control region of the brain, appeared to be activated in tandem with the dorsal anterior cingulate cortex, which is part of the salience network and plays a role in focusing of attention. By contrast, there was little functional connectivity between these two areas of the brain in those with low hypnotizability.