Deep posteromedial cortical rhythm in dissociation
Nature September 16, 2020 Sam Vesuna, Isaac Kauvar, Ethan B Richman et al. 291 citations
A 1–3-Hz rhythm in deep posteromedial cortex underlies dissociative states in both mice and humans. In mice, precisely-dosed ketamine or phencyclidine induced this rhythm in layer 5 neurons of the retrosplenial cortex, which coupled with thalamus circuitry but uncoupled from most other brain regions. Rhythmic optogenetic activation of these neurons recapitulated dissociation-like behaviors. Local HCN1 pacemakers were required for ketamine to induce the rhythm and behavioral effects. In a patient with focal epilepsy, a similar localized rhythm in the homologous deep posteromedial cortex correlated with pre-seizure self-reported dissociation, and electrical stimulation of this region elicited dissociative experiences.