Neural correlates of the DMT experience as assessed via multivariate EEG

Abstract

Studying transitions in and out of the altered state of consciousness caused by intravenous (IV) N,N-Dimethyltryptamine (DMT -a fast-acting tryptamine psychedelic) offers a safe and powerful means of advancing knowledge on the neurobiology of conscious states. Here we sought to investigate the effects of IV DMT on the power spectrum and signal diversity of human brain activity (6 female, 7 male) recorded via multivariate EEG, and plot relationships between subjective experience, brain activity and drug plasma concentrations across time. Compared with placebo, DMT markedly reduced oscillatory power in the alpha and beta bands and robustly increased spontaneous signal diversity. Time-referenced analyses revealed close relationships between changes in various aspects ofsubjective experience and changes in brain activity. Importantly, the emergence of oscillatory activity within the delta and theta frequency bands was found to correlate with the peak of the experience, and particularly its eyes-closed visual component. These findings highlight marked changes in oscillatory activity and signal diversity with DMT that parallel broad and specific components of the relevant subjective experience and thus further our understanding of the neurobiological underpinnings of immersive states of consciousness.

Classic Psychedelic Drugs: Update on Biological Mechanisms

“…Recent empirical research has identified increased entropy or signal diversity as a signature of psychedelic states 149 . Recent neuroimaging studies with magnetoencephalography (MEG) and EEG showed that LSD, psilocybin, and DMT increased the Lempel-Ziv complexity, a measure of signal diversity and approximation to entropy, which correlated with the overall intensity of the psilocybin and DMT-induced psychedelic experience 150 151 . Furthermore, in an fMRI study, LSD increased sample entropy in sensory and some higher-order networks 80 .…”

Taking Different Roads: l‐Tryptophan as the Origin of Psilocybe Natural Products

“…and is rapidly metabolized when administered parenterally. [26] Bufotenin is best known as a toad poison, but has also been isolated from Scheme 1. Overview on l-tryptophan-fed natural product pathways in Psilocybe sp.…”

“…While DMT is known to elicit a psychedelic effect in humans, the compound is not orally active in the absence of monoamine oxidase inhibitors (see also section 2.3.) and is rapidly metabolized when administered parenterally [26] . Bufotenin is best known as a toad poison, but has also been isolated from Anandenanthera trees (legumes), and from the mushroom Amanita citrina (false death cap).…”

A Review on Research and Evaluation Methods for Investigating Self-Transcendence

“…However, the interviewer needs to be highly trained in the interviewing technique to ensure reliability. Microphenomenology has been used to study awe Stepanova et al, 2019), meditative experiences (Petitmengin et al, 2017;Prpa et al, 2018;Przyrembel and Singer, 2018), and altered states of consciousness caused by DMT-a fast-acting tryptamine psychedelic (Timmermann et al, 2019). Both phenomenology and microphenomenology can be useful in describing self-transcendence, but which one you use depends on if you want to study the experience generally and across life times (phenomenology), or if you want to look at one specific experience in great detail (microphenomenology).…”