medRxiv
October 13, 2024
Brian S. Barnett
preprint
A survey of researchers who published the most-cited psychedelics articles since 2000 found that federal grant applications for therapeutic psychedelic research at the National Institutes of Health (NIH) had a 16.7% funding rate, lower than the NIH's 23.4% average for R-01 equivalent grants from 1998 to 2023. No applications submitted before 2006–2010 were funded, but the rate since then (estimated at 19.05% to 22.2%) is close to the NIH's average annual rate of 20.6% for those years. Respondents believed the funding landscape has improved recently.
medRxiv
June 20, 2024
Dimy Fluyau, Vasanth Kattalai Kailasam, Neelambika Revadigar
preprint
Psilocybin produced a rapid and sustained reduction in depressive and anxiety symptoms in patients with major depressive disorder and in those with life-threatening cancer. MDMA reduced depressive symptoms in patients with life-threatening cancer, autism spectrum disorder, and post-traumatic stress disorder, and reduced social anxiety, but its effect on anxiety symptoms overall was negligible or negative. Ayahuasca reduced depressive symptoms in individuals with treatment-resistant major depressive and personality disorders. LSD reduced anxiety symptoms in individuals with life-threatening cancer. Adverse effects included elevated blood pressure, headaches, and panic attacks for psilocybin and MDMA, plus feeling cold for MDMA.
medRxiv
May 10, 2023
Victoria di Virgilio, Amir Minerbi, Jagpaul Kaur Deol et al.
preprint
Veterans and civilians who used psychedelic medicines for non-recreational purposes in the previous three years reported improvements across pain, mental health, function, and overall quality of life, with the largest perceived gains in mental health and quality of life and the smallest in pain. Correlations among these domains were highly significant, particularly between function, quality of life, and mental health. No significant differences emerged between specific psychedelic drugs, suggesting the benefits may be class-wide. The study was retrospective, anonymous, and relatively small (65 participants), and lacked a baseline comparison.
medRxiv
June 16, 2022
Caroline L. Alves, Thaise G. L. de O. Toutain, Joel Augusto Moura Porto et al.
preprint
A machine-learning method using support vector machines classified EEG data from volunteers before and after inhaling the psychedelic DMT. Complex network measures derived from brain connectivity achieved 89% AUC, outperforming raw connectivity matrices. Key distinguishing features included connections between temporal and central cortex regions (TP8-C3) linked to finger movements, and between precentral gyrus and lateral occipital cortex (FC5-P8) potentially related to emotional and mystical experiences. Closeness centrality was the most important network measure. DMT increased community size and average path length, disrupting the balance between functional segregation and integration, supporting the idea that cortical activity becomes more entropic under psychedelics.
medRxiv
March 2, 2022
Maggie Kiraga, Kim P. C. Kuypers, Malin V. Uthaug et al.
preprint
In a group of 52 healthy volunteers attending psilocybin ceremonies, consuming an average of 27.1 mg of psilocin led to medium to large reductions in both state and trait anxiety that persisted for at least one week. One week after the ceremony, participants showed increased non-judging mindfulness and decreased neuroticism. The strongest predictors of reduced trait anxiety were lower neuroticism, and for state anxiety, higher ego dissolution during the experience. The findings suggest rapid and lasting anxiolytic effects of psilocybin in a supportive setting, but further research is needed to confirm these effects in clinical populations.
medRxiv
Klemens Egger, Daniel Meling, Firuze Polat et al.
preprint
In a double-blind, placebo-controlled pharmaco-fMRI study, 40 meditation practitioners on a three-day retreat received either placebo or buccal DMT-harmine (120 mg each). Meditation alone increased network segregation across several resting-state networks, while DMT-harmine increased functional connectivity within the visual network and between visual and attention networks. Between-group differences showed increased connectivity between visual and salience networks in the DMT-harmine group. No prolonged cortical gradient disruption was observed, indicating a return to typical brain organization shortly after the experience. Meditation reduced connectivity between networks, whereas DMT-harmine increased within- and between-network connectivity, revealing distinct neural mechanisms.