Was it a vision or a waking dream?

Abstract

Comments on an article by Guillaume Herbet et al. (see record 2014-11053-026). Reminiscent of Wilder Penfiel’s famous experiments, Neurologists in France have reported a remarkable case in which intraoperative electrical stimulations of the posterior cingulate cortex (PCC) in a conscious patient induced transient dreamlike states with vivid visual imagery. We were fascinated to read the casereport of a dreamlike experience evoked by direct electrical stimulation of the posterior cingulate cortex (PCC) in an epilepsy patient by Herbet et al. In summary, we were struck by similarities between Herbet et al.’s findings with direct electrical stimulation of the PCC and those of our own with psilocybin and neuroimaging. Their case provides some causative support for the notion that the PCC is centrally involved in mediating the quality of consciousness, and more specifically, that inhibiting the PCC/disrupting DMN activity can induce dreamlike states. Moreover, we are intrigued by the possibility that drug and stimulation-induced dreamlike states are indeed truly dreamlike, i.e., in the neurophysiological sense as well as the phenomenological.