Microglia, the brain's resident immune cells, are emerging as a key target for new psychiatric drugs. This review examines how psychedelics (psilocybin, LSD), ketamine, and propofol interact with microglia to produce therapeutic effects. The authors detail pathways including sigma-1 receptors, serotonin and GABA signaling, and tryptophan metabolism through which these agents modulate microglial activity and inflammation, likely contributing to their benefits in mood disorders and addiction. The paper also discusses future directions, including implications for aging, glial cell heterogeneity, and advanced research methods.
In patients with severe brain injury, the neurological wake-up test—a brief interruption of sedation to check responsiveness—often yields ambiguous or absent behavioral responses, limiting its prognostic value. Recording 128-channel EEG from 41 such patients during propofol sedation interruption revealed that brain responses, measured by EEG power, spatial ratios, and the spectral exponent, can show signs of waking even when behavior does not. Combining EEG with behavioral assessment improved predictions of survival, recovery of consciousness, and long-term functional outcomes, outperforming the predictions of attending physicians. EEG can complement the wake-up test to better inform clinicians, families, and treatment planning.