An EEG-Based Evaluation of Antidepressant Effects of Ketamine Enantiomers and Metabolites in Monkeys

Ketamine has shown promise as a rapid-acting antidepressant, but its mechanisms of action and optimal formulation remain incompletely understood. Iwamura et al. ( J Neurophysiol 135: 935–950, 2026) used electroencephalography (EEG), a measure of brain electrical activity, to compare how ketamine enantiomers and metabolites differ in their effects on brain activity in a primate model. This mini-review summarizes their findings and examines how this work may inform future research and advance understanding of ketamine-based treatments for depression.