Effective Connectivity of Functionally Anticorrelated Networks Under Lysergic Acid Diethylamide.
Devon Stoliker, Leonardo Novelli, Franz X Vollenweider, Gary F Egan, Katrin H Preller, Adeel Razi
Biological psychiatry February 1, 2023 DOI: 10.1016/j.biopsych.2022.07.013 via PubMed
Summary
AI-generated from the abstractUnder the peak effect of LSD, the inhibitory influence from the salience network to the default mode network becomes excitatory, and inhibition from the default mode network to the dorsal attention network weakens. These changes in effective connectivity between resting-state networks may reduce their normal anticorrelation, offering a neural mechanism for ego dissolution—the blurring of the boundary between self and world. The findings suggest that alterations in the sense of self across different conscious states depend on the organized balance of effective connectivity among these networks.
Study at a glance
| Characteristics | Experimental study with placebo control Peer reviewed |
|---|---|
| Sample size | 25 |
| Population | Healthy adults |
| Intervention | Lysergic acid diethylamide (LSD) |
| Dose | 100 μg |
| Topics | Ego dissolution LSD |
| Keywords | Anticorrelated networks Dynamic causal modeling Effective connectivity Psychedelics LSD |
| Citations | 49 |
| Key finding | LSD transforms inhibitory effective connectivity from the salience network to the default mode network into excitatory connectivity and reduces inhibition from the default mode network to the dorsal attention network, potentially underlying ego dissolution. |
Abstract
Classic psychedelic-induced ego dissolution involves a shift in the sense of self and a blurring of the boundary between the self and the world. A similar phenomenon is identified in psychopathology and is associated with the balance of anticorrelated activity between the default mode network, which directs attention inward, and the salience network, which recruits the dorsal attention network to direct attention outward. To test whether changes in anticorrelated networks underlie the peak effects of lysergic acid diethylamide (LSD), we applied dynamic causal modeling to infer effective connectivity of resting-state functional magnetic resonance imaging scans from a study of 25 healthy adults who were administered 100 μg of LSD or placebo. We found that inhibitory effective connectivity from the salience network to the default mode network became excitatory, and inhibitory effective connectivity from the default mode network to the dorsal attention network decreased under the peak effect of LSD. The effective connectivity changes we identified may reflect diminution of the functional anticorrelation between resting-state networks that may be a key neural mechanism of LSD and underlie ego dissolution. Our findings suggest that changes to the sense of self and subject-object boundaries across different states of consciousness may depend upon the organized balance of effective connectivity of resting-state networks.