NeuroImage
June 1, 2023
Rui Dai, Tony E Larkin, Zirui Huang et al.
49 citations
Three different psychedelics—nitrous oxide, ketamine, and lysergic acid diethylamide—produce a common pattern of brain network changes despite having distinct molecular mechanisms and delivery methods. Each drug reduced connectivity within brain networks and enhanced connectivity between networks. Specifically, all three increased connections between the right temporoparietal junction and bilateral intraparietal sulcus, and between the precuneus and left intraparietal sulcus. These regions lie within the posterior cortical "hot zone," an area thought to mediate the qualitative aspects of experience. The findings identify a biologically plausible candidate for the subjective effects of both classical and non-classical psychedelics.
Current Biology
December 1, 2023
Nicholas Kolbman, Tiecheng Liu, Peter Guzzo et al.
21 citations
A single intravenous dose of psilocybin reduces mechanical hypersensitivity for 28 days in a rat model of formalin-induced chronic pain, suggesting potential for treating chronic pain conditions. The study addresses a gap in research on psilocybin's effectiveness for chronic pain, as prior work focused on psychiatric disorders and substance abuse. No systematic investigation had previously examined psilocybin's impact on chronic pain indices.
Scientific reports
January 6, 2023
Nicolas G Glynos, Lily Carter, Soo Jung Lee et al.
17 citations
Indolethylamine N-methyltransferase (INMT) is an enzyme known for producing the psychedelic compound DMT in mammalian brains. Researchers created INMT-knockout rats to determine whether INMT is necessary for DMT production. Brain and lung tissues from both normal and INMT-knockout rats showed equal levels of tryptamine-dependent activity, but the resulting products were neither NMT nor DMT. Rat INMT alone was also insufficient for producing NMT or DMT. These findings indicate an alternative enzymatic pathway for DMT biosynthesis exists in rats, motivating further investigation into how mammals produce DMT naturally.
bioRxiv : the preprint server for biology
February 15, 2025
Nicolas G Glynos, Emma R Huels, Amanda Nelson et al.
11 citations
preprint
Intravenous DMT in rats caused dose-dependent increases in serotonin and dopamine in the medial prefrontal and somatosensory cortices, along with changes in brain wave patterns: reduced theta and low gamma power, increased delta, medium gamma, and high gamma power, and altered functional connectivity. All doses produced head twitch responses, most after the low dose. For the first time, endogenous DMT was measured in these cortical sites at levels comparable to serotonin and dopamine, suggesting a physiological role for the compound. The findings point to shared mechanisms with other psychedelics and support DMT's potential for treating psychiatric disorders.
Translational Psychiatry
March 25, 2025
Brian H Silverstein, Nicholas Kolbman, Amanda Nelson et al.
8 citations
Psilocybin alters brain network organization in rats in a dose-dependent manner. Using electroencephalography from 27 cortical sites in 12 rats, the study found that psilocybin disrupted theta-gamma coupling, increased frontal high gamma connectivity and network density, and increased posterior theta connectivity and density. Medium gamma frontoparietal connectivity and behavioral activity showed an inverted-U relationship with dose. These results suggest that high-frequency network organization, decoupled from local theta-phase, may be a key signature of psilocybin-induced altered states of consciousness.
Anesthesiology
June 1, 2024
George A Mashour, UnCheol Lee, Dinesh Pal et al.
8 citations
Near-death experiences have been reported since antiquity and often involve perceptions of light, interactions with entities, and life recall. After in-hospital cardiac arrest, such experiences occur in 10 to 20% of cases. Recent neurophysiologic evidence suggests a surge of gamma oscillations and increased cortical connectivity following cardiac and respiratory arrest, offering a biological basis for this conscious experience.
Sleep
May 26, 2025
Alejandra Mondino, Amir Jadidian, Brandon A Toth et al.
4 citations
The preoptic area of the hypothalamus, long thought to only promote sleep, contains glutamatergic neurons (MLPO_VGLUT2) that actually drive wakefulness and suppress REM sleep. Using fiber photometry in mice, these neurons were highly active during REM sleep, wakefulness, and brief arousals, but minimally active during non-REM sleep. Chemogenetic stimulation of MLPO_VGLUT2 inhibited REM sleep onset, independent of non-REM fragmentation caused by hypothermia, and blocked the REM sleep rebound normally seen after total sleep deprivation. Chemogenetic inhibition increased REM sleep time only during the light phase. Mapping showed these neurons project to brain regions that promote wakefulness and inhibit REM sleep. The authors conclude that MLPO_VGLUT2 powerfully suppress REM sleep, and their overactivation disrupts REM recovery.
bioRxiv (Cold Spring Harbor Laboratory)
February 12, 2024
Brian H Silverstein, Nicholas Kolbman, Amanda Nelson et al.
3 citations
preprint
Psilocybin disrupts the coupling between theta and gamma brain waves in rats and reorganizes brain networks in a dose-dependent manner. Using 27 electrodes across the cortex, the study found that psilocybin increased frontal high gamma connectivity and posterior theta connectivity, as well as network density in those regions. Medium gamma frontoparietal connectivity showed a nonlinear relationship with dose. Theta-gamma phase-amplitude coupling was disrupted. These changes suggest that high-frequency network organization, decoupled from local theta-phase, may be a signature of the altered state of consciousness induced by psilocybin.
JAMA psychiatry
June 1, 2026
Ben Deverett, Duan Li, Theresa R Lii et al.
1 citation
Ketamine produces distinct brain-wave patterns that may be linked to its therapeutic effects. General anesthesia selectively blocks one of these patterns—theta oscillations—while leaving another pattern, beta-gamma oscillations, intact. In 52 participants, ketamine given during anesthesia preserved beta-gamma power increases but eliminated the characteristic theta augmentation seen during awake administration. This suggests that different neurophysiologic effects of ketamine can be separated, offering a way to investigate which brain-wave changes underlie its antidepressant, analgesic, or dissociative properties.
Journal of psychopharmacology (Oxford, England)
May 1, 2025
Niloufar Pouyan, Jacob S Aday, Steven E Harte et al.
1 citation
People with treatment-resistant conditions often see their illness as part of their identity. The pictorial representation of illness and self measure (PRISM) gauges this self-condition enmeshment. In a survey of 297 individuals who used psychedelics therapeutically on their own, most reported symptom improvement: 95.4% with depression, 98.36% with posttraumatic stress disorder, and 94.87% with anxiety. PRISM scores dropped significantly after the most salient psychedelic experience, indicating reduced identification with the condition. The decrease in PRISM scores correlated with symptom improvement across all conditions. PRISM appears useful for tracking how psychedelics affect self-perception across diagnoses, though limitations include convenience sampling, potential positive bias, and retrospective reporting.
bioRxiv : the preprint server for biology
October 23, 2024
Rui Dai, Hyunwoo Jang, Anthony G Hudetz et al.
1 citation
preprint
Consciousness appears to depend on global interactions across multiple brain regions rather than on localized neural activity. Using fMRI data across psychedelic, sleep, and deep sedation states, the study found a mirror-image pattern: psychedelic states increased global functional connectivity and decreased local neural synchrony, while non-REM sleep and deep sedation showed the opposite pattern. This pattern was observed in anterior-posterior and posterior-posterior brain regions but not within the anterior brain alone. Anterior transmodal regions were key for anterior-posterior connectivity, while posterior transmodal and unimodal regions were critical for posterior-posterior connectivity. The findings support global theories of consciousness and bridge the Global Neuronal Workspace hypothesis and Integrated Information Theory by showing shared neural mechanisms.
bioRxiv : the preprint server for biology
June 1, 2026
Panagiotis Fotiadis, Hyunwoo Jang, Rui Dai et al.
Brain waves coordinate neural communication and shape conscious perception. Analyzing blood oxygen level-dependent activity from the Human Connectome Project and other datasets across sleep, propofol anesthesia, and psychedelic states (LSD, DMT, psilocybin, nitrous oxide, ketamine), four dominant wave propagation motifs were identified: a global synchronized wave, an anti-correlated unimodal-transmodal wave, an anti-correlated task-positive/task-negative wave, and an anti-correlated visual-somatomotor wave.