DMT-induced shifts in criticality correlate with ego-dissolution
bioRxiv – February 08, 2025
Source: medRxiv/bioRxiv/arXiv
Summary
Psychedelics like DMT can significantly change our perception and brain function. This study reveals that DMT alters brain oscillations, moving them away from a balanced state known as criticality. Notably, this shift correlates with feelings of ego-dissolution, suggesting new insights into how psychedelics influence consciousness.
Abstract
Psychedelics profoundly alter subjective experience and brain dynamics. Brain oscillations express signatures of near-critical dynamics, relevant for healthy function. Alterations in the proximity to criticality have been suggested to underlie the experiential and neurological effects of psychedelics. Here, we investigate the effects of a psychedelic substance (DMT) on the criticality of brain oscillations, and in relation to subjective experience. We find that DMT shifts the dynamics of brain oscillations away from criticality in alpha and adjacent frequency bands. In this context, entropy is increased while complexity is reduced. We find that the criticality shifts observed in alpha and theta bands correlate with the intensity ratings of ego-dissolution, a hallmark of psychedelic experience. Finally, using a recently developed metric, the functional excitatory-inhibitory ratio, we find that the DMT-induced criticality shift in brain oscillations is towards subcritical regimes. These findings have major implications for the understanding of psychedelic mechanisms of action in the human brain and for the neurological basis of altered states of consciousness.