bioRxiv Preprint Server
April 18, 2024
Melanie Boly, Richard Smith, Giulietta Vigueras Borrego et al.
5 citations
preprint
A state called pure presence, reported in meditative traditions as a vivid experience without thoughts, perceptions, or self, was examined in twenty-two long-term meditators using high-density EEG. During pure presence, brain activity showed widespread reductions in gamma and delta power compared to mind-wandering, watching a movie, active thinking, and dreamless sleep. The strongest gamma decreases occurred in the posteromedial cortex. These findings align with integrated information theory's prediction that vivid consciousness can arise when the brain's cortical substrate is largely quiet yet highly awake.
bioRxiv (Cold Spring Harbor Laboratory)
June 13, 2024
Christopher R. Nicholas, Matthew I. Banks, Richard Lennertz et al.
3 citations
preprint
Co-administering the amnestic benzodiazepine midazolam with psilocybin in 8 healthy participants partially impaired memory for the psychedelic experience while still allowing a conscious experience to occur. The degree of memory impairment was inversely associated with salience, insight, and well-being induced by psilocybin. These results suggest that memory of the acute psychedelic experience contributes to therapeutically relevant behavioral effects. Because midazolam blocks memory by blocking cortical neural plasticity, it may also help evaluate how the pro-neuroplastic properties of psychedelics contribute to their therapeutic activity.
bioRxiv (Cold Spring Harbor Laboratory)
July 29, 2025
May Kung Sutherland, Christopher R. Nicholas, Richard Lennertz et al.
preprint
Psilocybin, a serotonergic psychedelic, induces neural plasticity and alters consciousness, while midazolam, a benzodiazepine, blunts plasticity and causes sedation and amnesia. In an open-label pilot study, 25 mg of oral psilocybin was given alongside intravenous midazolam at doses that allowed a full psychedelic experience but reduced memory of it. EEG recordings showed that 15-30 minutes after dosing, when midazolam was at its target concentration, beta power increased and the spectral exponent decreased. As psilocybin's effects emerged over the next six hours, Lempel-Ziv complexity and spectral exponent increased while broadband power decreased. These findings suggest psilocybin's effects persist even with midazolam, supporting its use in mechanistic studies.