Characterizing ketamine-induced dissociation using human intracranial neurophysiology: brain dynamics, network activity, and interactions with propofol
bioRxiv Preprint Server May 2, 2022 Fangyun Tian, Laura D. Lewis, David W. Zhou et al. preprint
A subanesthetic dose of ketamine increases gamma oscillations in the prefrontal cortex and hippocampus, brain areas linked to its rapid antidepressant effects, and produces a 3 Hz oscillation in the posteromedial cortex that may underlie its dissociative effects. By adding propofol, which blocks NMDA-mediated disinhibition and shares HCN1 inhibition with ketamine, the study distinguished brain dynamics caused by NMDA-mediated disinhibition from those caused by HCN1 inhibition. The results suggest ketamine engages distinct neural circuits in frequency-dependent patterns to produce antidepressant and dissociative effects, potentially guiding development of new depression therapies with fewer side effects.