Evidence that Subanesthetic Doses of Ketamine Cause Sustained Disruptions of NMDA and AMPA-Mediated Frontoparietal Connectivity in Humans
Journal of Neuroscience August 19, 2015 Suresh Muthukumaraswamy, Alexander D. Shaw, Laura E. Jackson et al. 244 citations
Subanesthetic doses of ketamine, similar to those used in antidepressant studies, increase anterior theta and gamma power but decrease posterior theta, delta, and alpha power, as shown by magnetoencephalographic recordings. Dynamic causal modeling revealed a decrease in NMDA and AMPA-mediated frontal-to-parietal connectivity, with AMPA-mediated changes persisting up to 50 minutes after infusion ceased, even after perceptual distortions had ended. A decrease in gain of parietal pyramidal cells correlated with participants' self-reports of blissful state. These alterations in frontoparietal connectivity patterns may be important in generating the antidepressant response to ketamine.