Each month our editorial team sifts through hundreds of papers and curates notable findings—for practitioners and informed readers who want to stay current with the evidence. Subscribe to the monthly Research Digest for expert analysis and concise summaries of key papers.
This paper is a meta-analysis of more than 300 studies in humans that looked at links between psychological stress and measures of the immune system. It found that very short, acute stressors (minutes) were tied to increases in some natural (innate) immune measures and decreases in some specific (adaptive) immune…
This umbrella review looked at the best existing reviews and large studies to see if depression is linked to low serotonin or low serotonin activity. Across measures of serotonin in fluids, receptor and transporter studies, tryptophan depletion experiments, and large genetic studies, the evidence was mixed or absent. The authors…
This multi-site, randomized, double-blind phase 3 trial tested MDMA-assisted therapy (MDMA-AT) versus placebo with the same therapy in 104 people with moderate to severe PTSD. Blinded assessors found larger average reductions in PTSD symptoms and in functional impairment for the MDMA-AT group than for the placebo group. The MDMA group…
This small randomized trial tested six IV ketamine infusions (0.5 mg/kg) given over 2 weeks versus midazolam (0.045 mg/kg) in 30 people with chronic PTSD. The ketamine group had larger drops in PTSD symptoms at 2 weeks, more people met the study’s response criteria, and ketamine was generally well tolerated.…
This review looked at many studies about classic psychedelics (like psilocybin and LSD), MDMA, ketamine, and plant medicines (like ayahuasca). The authors explain how these drugs can change the brain’s wiring, calm inflammatory processes, and shift key brain chemicals. Those actions may help explain why small clinical trials and animal…
A single dose of psilocybin, a psychedelic that acutely causes distortions of space-time perception and ego dissolution, produces rapid and persistent therapeutic effects in human clinical trials1-4. In animal models, psilocybin induces neuroplasticity in cortex and hippocampus5-8. It remains unclear how human brain network changes relate to subjective and lasting…
This systematic review looked at 83 published reports on ketamine for mental health and substance use disorders. It found strong evidence that ketamine can produce rapid antidepressant and anti‑suicidal effects, but these benefits tend to be short‑lived. Evidence for other conditions was weaker but often showed similar short-term effects. Many…
This 2018 review looked at animal and human studies of ketamine as a possible treatment for addiction. Early findings are promising: some studies found ketamine helped people stay abstinent from alcohol and heroin and reduced cocaine craving and use. However, the authors say the research is still new, many studies…
The researchers repeatedly measured early-morning cortisol and self-reported depressive symptoms in a population of adolescents. Using a statistical method to find subgroups, they identified a high-risk group (17% of the sample) with both high depressive symptoms and elevated morning cortisol. Membership in this group was linked to worse autobiographical memory…
This 2022 review looks at studies linking stress, inflammation, and changes in the amygdala to depression and anxiety. It says stress can trigger inflammation in the body and brain, that inflammation can change neurons and circuits in the amygdala, and that these changes are linked to depression- and anxiety-like signs…
Attention-deficit/hyperactivity disorder (ADHD) is a prevalent and serious neurodevelopmental disorder characterized by symptoms of inattention and/or hyperactivity/impulsivity. Chronic and childhood stress is involved in ADHD development, and ADHD is highly comorbid with anxiety. Similarly, inflammatory diseases and a pro-inflammatory state have been associated with ADHD. However, while several works have…
This review looks at research on psychedelic drugs, especially psilocybin. It says recent human studies show a single dose can give lasting relief from severe depression, and regulators have given two late-stage psilocybin trials special 'Breakthrough Therapy' status. The paper also pulls together lab and animal studies that suggest psychedelics…
