Divergent effects of ketamine and psilocybin on EEG power spectral density in a mismatch negativity paradigm
Psychopharmacology November 5, 2025 Milad Soltanzadeh, Wang Zheng, Shona G. Allohverdi et al. 1 citation
Ketamine and psilocybin, two drugs with therapeutic potential for depression, produce distinct effects on brain electrical activity. Ketamine disrupts the balance between excitation and inhibition in neural circuits, as shown by changes in the aperiodic components of EEG spectra, and reduces beta band activity. Psilocybin also reduces alpha power in similar brain regions but does not affect beta activity or aperiodic components in the same way. These differences reflect their different mechanisms: ketamine blocks NMDA receptors while psilocybin targets serotonin receptors. Ketamine's unique EEG signature supports its role as a model for prodromal psychosis.