Effects of classic psychedelic drugs on turbulent signatures in brain dynamics

CRUZAT, JOSEPHINE; PERL, YONATAN SANZ; ESCRICHS, ANIRA; VOHRYZEK, JAKUB; TIMMERMANN, CHRISTOPHER; ROSEMAN, LEOR; LUPPI, ANDREA I.; IBAÑEZ, AGUSTIN; NUTT, DAVID; CARHART-HARRIS, ROBIN; TAGLIAZUCCHI, ENZO; DECO, GUSTAVO; KRINGELBACH, MORTEN L.

Network Neuroscience

The MIT press

Año: 2022 p. 1 - 21

Psychedelic drugs show promise as safe and effective treatments for neuropsychiatric disorders,yet their mechanisms of action are not fully understood. A fundamental hypothesis is thatpsychedelics work by dose-dependently changing the functional hierarchy of brain dynamics,but it is unclear whether different psychedelics act similarly. Here, we investigated the changes inthe brain’s functional hierarchy associated with two different psychedelics (LSD and psilocybin).Using a novel turbulence framework, we were able to determine the vorticity, that is, the locallevel of synchronization, that allowed us to extend the standard global time-based measure ofmetastability to become a local-based measure of both space and time. This framework produceddetailed signatures of turbulence-based hierarchical change for each psychedelic drug, revealingconsistent and discriminate effects on a higher level network, that is, the default mode network.Overall, our findings directly support a prior hypothesis that psychedelics modulate (i.e.,“compress”) the functional hierarchy and provide a quantification of these changes for twodifferent psychedelics. Implications for therapeutic applications of psychedelics are discussed.