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.
Frontiers in psychology
January 1, 2025
Emma R Huels, Lily Carter, Gang Xu et al.
Shamanic journeying, an ancient spiritual practice, produces dynamic changes in heart function measurable through heart rate variability (HRV). In a single subject, drumming initiation decreased heart rate and increased HRV measures, while shapeshifting increased heart rate and certain HRV indicators. Qigong meditation also increased HRV measures, with greater changes in some metrics than drumming initiation. These findings suggest shamanic journeying involves widespread cardiac and physiological changes that can be tracked visually and via ultra-short-term HRV.
Research square
January 12, 2026
Niloufar Pouyan, Chelsea M Kaplan, Tony E Larkin et al.
Subanesthetic nitrous oxide (N2O) alters visual experience by reconfiguring large-scale brain networks rather than changing early visual processing. In a placebo-controlled fMRI study with 13 healthy adults, participants viewed a flashing checkerboard and rated visual intensity and unpleasantness. Increased unpleasantness under N2O was linked to reduced connectivity between the right anterior insula and the anterior cingulate cortex and lateral occipital cortex. Network analyses revealed reduced modularity and a collapse of hierarchical organization, with sensorimotor connectivity redistributed toward salience and associative networks. These findings suggest that altered visual experience under N2O arises from disrupted salience integration and increased cross-network communication.