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.
Our findings suggest that geographic location plays a limited role in the reasons for the large variability of ADHD/HD prevalence estimates worldwide. Instead, this variability seems to be explained primarily by the methodological characteristics of studies.
In a small, carefully controlled study, seven people with major depression each received a single low-dose ketamine infusion on one day and a saline infusion on another day, without anyone knowing which was which. People who got ketamine showed clear improvement in their depressive symptoms within three days, while those…
In a small, controlled study of 18 people with treatment-resistant major depression, a single intravenous dose of the NMDA receptor antagonist ketamine (0.5 mg/kg) produced rapid drops in depression scores. Improvement began within about 2 hours and remained statistically significant compared with placebo for up to 1 week. The study…
The WHO Adult ADHD Self-Report Scale (ASRS) has 18 questions about recent ADHD symptoms, and a shorter six-question screener was tested against blind clinical diagnoses in 154 people from the US National Comorbidity Survey Replication. Each ASRS item was linked to the clinical rating, but agreement varied a lot across…
This U.S. study used a nationally representative household survey of 3,199 adults aged 18–44, plus clinical follow-up interviews, to measure adult ADHD. Researchers estimated that 4.4% of adults had current ADHD. Adult ADHD was more common in men, people who were previously married, those who were unemployed, and non-Hispanic white…
Some research suggests that whole-plant cannabis compounds (like THC, CBD, other cannabinoids, terpenes, and flavonoids) can interact so the plant’s effects differ from CBD alone. Healthline explains three CBD types — full-spectrum, broad-spectrum, and isolate — and notes legal, safety, and labeling limits. The article says there is evidence for…
Researchers tested a single intravenous dose of ketamine in 73 people with major depression that had not gotten better with usual treatments. In a two-site, double-blind trial, people were randomly given either ketamine or an active placebo (the anesthetic midazolam). Twenty-four hours after the infusion, people who got ketamine were…
The endocannabinoid system (ECS) is a widespread brain signaling system made of cannabinoid receptors, naturally made lipid messengers, and the enzymes that make and break those messengers. The two best-studied messengers are 2-AG and anandamide, and they are produced and degraded by different enzyme pathways. CB1 receptors are common in…
This review looked at research on emotion dysregulation (problems managing emotions) in people with ADHD. It found three main points: emotion dysregulation is common across the lifespan and causes substantial problems; it may come from trouble noticing, recognizing, or paying attention to emotional cues tied to a brain circuit that…
This 12-week randomised trial tested a structured dietary program (a modified Mediterranean-style diet) against a social-support control in adults with moderate to severe major depression. Sixty-seven people were randomised (33 to diet, 34 to control). The diet group showed larger drops in depressive symptoms on the MADRS scale at 12…
Researchers tested a nasal spray form of esketamine together with a newly started oral antidepressant in adults whose depression had not improved after trying at least two antidepressants. Over four weeks, people who got esketamine plus a new antidepressant had faster and larger drops in depression symptoms than those who…
This umbrella review pooled evidence from 97 systematic reviews (1,039 randomized trials, 128,119 participants) to examine whether physical activity affects symptoms of depression, anxiety and psychological distress in adults. Overall, physical activity produced medium-sized reductions in symptoms (median effect size for depression = -0.43, for anxiety = -0.42; distress effect…
