Frontiers in Systems Neuroscience
March 21, 2022
Andrea Zaccaro, Andrea Piarulli, Lorenza Melosini et al.
32 citations
Slow nasal breathing at 2.5 breaths per minute, as practiced in Pranayama, alters brain activity and induces a non-ordinary state of consciousness, primarily through mechanical stimulation of the olfactory epithelium rather than through vagal nerve stimulation. In 12 experienced meditators, slow nasal breathing produced slowing of EEG delta and theta activity in prefrontal regions, widespread increases in theta and high-beta connectivity, increased phase-amplitude coupling between these bands in prefrontal and posterior Default Mode Network regions, and increased small-worldness of high-beta networks. Participants reported a higher perception of being in a non-ordinary state of consciousness compared to mouth breathing at the same rate or resting state.
Journal of Cognitive Neuroscience
January 1, 2023
Rajanikant Panda, Audrey Vanhaudenhuyse, Andrea Piarulli et al.
15 citations
During hypnosis, brain connectivity changes in ways that suggest more efficient cognitive processing and less mind-wandering. In nine healthy participants, hypnosis increased delta-wave connections between frontal brain regions and between frontal and parietal regions. It decreased alpha and beta-2 connections among frontal, parietal, and midline areas. Network analysis showed greater segregation of short-range connections in delta and alpha bands and greater integration of long-range connections in beta-2 bands. Frontal and right parietal electrodes became central hubs. These altered dynamics may reflect a modified balance between internal and external awareness networks.
Brain Structure and Function
January 1, 2021
Jitka Annen, Rajanikant Panda, Charlotte Martial et al.
15 citations
A world champion free diver's brain activity and connectivity shift markedly during a 6.5-minute breath-hold. EEG shows increased alpha wave power and connectivity, with decreased delta band connectivity. fMRI reveals heightened connectivity within the default mode network and visual areas, but reduced connectivity in sensorimotor cortices. These changes overlap with some meditation-related brain signatures but also include unique features suggesting altered somatosensory integration. Self-reports indicate that elite free divers may achieve a state of sensory dissociation during prolonged apnea, reflecting their ability to adapt psychologically and physiologically to extreme breath-holding.
International journal of yoga therapy
January 1, 2021
Andrea Zaccaro, André Riehl, Andrea Piarulli et al.
13 citations
Yoga nidra, an ancient meditative practice, induces an altered state of consciousness distinct from sleep. In a preliminary study, six healthy volunteers completed 12 guided sessions during a retreat. EEG recordings showed no sleep markers (K-complexes or spindles) during practice. Compared to a resting baseline, participants reported increased dissociative effects, altered body image, reduced rational thinking, and less volitional thought control. One subject's EEG analysis revealed early increases in alpha, beta, and theta power followed by reductions, with gamma power rising in later stages. These findings suggest yoga nidra produces a unique psychophysiological state, though larger studies are needed.
NeuroImage
September 1, 2024
Charlotte Martial, Andrea Piarulli, Olivia Gosseries et al.
10 citations
During fainting, some people have dream-like experiences with extraordinary, mystical features similar to near-death experiences. In 22 healthy volunteers who fainted under controlled conditions, eight reported such near-death-like features. Their brain activity showed higher electrical activity in delta, theta, and beta2 frequency bands in temporal and frontal regions, including the insula, right temporoparietal junction, and cingulate cortex. The richer the experience, the stronger the activity in these areas. The brains of those with near-death-like experiences also showed more complex, more connected, and more integrated neural networks compared to those without such experiences. These surges of neural activity may mark disconnected consciousness during fainting.
iScience
January 17, 2025
Paolo Cardone, Arthur Bonhomme, Vincent Bonhomme et al.
9 citations
In a small double-blind, placebo-controlled, cross-over trial with three adults who had prolonged disorders of consciousness after a coma, an intravenous sub-anesthetic dose of the atypical psychedelic ketamine increased brain complexity as measured by Lempel-Ziv complexity, but did not change the explainable consciousness indicator. Patients showed reduced spastic paresis and spent more time with their eyes open, yet their diagnosis of consciousness did not improve. No adverse effects occurred. The findings suggest a potential therapeutic role for ketamine in disorders of consciousness and support a link between brain complexity and conscious states.
bioRxiv Preprint Server
March 21, 2022
Danilo Menicucci, Valentina Cesari, Enrico Cipriani et al.
preprint
The fragmented sleep, fragmented mind hypothesis links sleep disturbances to dissociative states in people with dissociative traits, supported by neurophysiological theories that altered states of consciousness may arise from disrupted functional interaction among brain modules due to inefficient sleep processes.