Ketamine can relieve symptoms of both unipolar and bipolar depression within hours, but its long-term antidepressant effects and safety profile remain unknown. Researchers at the National Institute of Mental Health are working to identify the neurobiological mechanisms and biomarkers of ketamine's antidepressant efficacy. Patients with a family history of alcohol use disorder respond better to ketamine's antidepressant effect than those without that genetic risk. Researchers use magnetic resonance spectroscopy to study glutamate changes in the prefrontal cortex during ketamine infusion. Recruiting and retaining patients for clinical trials is difficult because participants must suspend their outside lives for three to six months.
Taking the hallucinogen psilocybin may boost positive feelings like bliss or a sense of oneness with the universe, but the authors question whether these feelings amount to genuine mystical experience or spiritual growth. The work examines the distinction between drug-induced altered states and authentic spiritual or mystical development, suggesting that the subjective experiences produced by psilocybin might not reflect true spiritual progress.