Modulating the default mode network using hypnosis.

Debate regarding the neural basis of the hypnotic state continues, but a recent hypothesis suggests that it may produce alterations in the default mode network (DMN). DMN describes a network of brain regions more active during low-demand compared to high-demand task conditions and has been linked to processes such as task-independent thinking, episodic memory, semantic processing, and self-awareness. However, the experiential and cognitive correlates of DMN remain difficult to investigate directly. Using hypnosis as a means of altering the resting ("default") state in conjunction with subjective measures and brain imaging, the authors found that the state of attentional absorption following a hypnotic induction was associated with reduced activity in DMN and increased activity in prefrontal attentional systems, under invariant conditions of passive visual stimulation. The findings that hypnosis and spontaneous conceptual thought at rest were subjectively and neurally distinctive are also relevant to understanding hypnosis itself.