Connectome-harmonic decomposition of human brain activity reveals dynamical repertoire re-organization under LSD.

LSD alters the energy and power of individual harmonic brain states in a frequency-selective manner, leading to an expansion of the repertoire of active brain states. This expansion is non-random, suggesting a general re-organization of brain dynamics. The frequency distribution of active brain states under LSD closely follows power-laws, indicating a re-organization of dynamics at the edge of criticality. These findings provide insight into how LSD affects brain function and open new methods for understanding complex brain dynamics in health and disease.

Study at a glance

Abstract

Recent studies have started to elucidate the effects of lysergic acid diethylamide (LSD) on the human brain but the underlying dynamics are not yet fully understood. Here we used 'connectome-harmonic decomposition', a novel method to investigate the dynamical changes in brain states. We found that LSD alters the energy and the power of individual harmonic brain states in a frequency-selective manner. Remarkably, this leads to an expansion of the repertoire of active brain states, suggestive of a general re-organization of brain dynamics given the non-random increase in co-activation across frequencies. Interestingly, the frequency distribution of the active repertoire of brain states under LSD closely follows power-laws indicating a re-organization of the dynamics at the edge of criticality. Beyond the present findings, these methods open up for a better understanding of the complex brain dynamics in health and disease.