Conclusions
To the best of our knowledge, this is the first study to examine the impact of LSD on whole-brain EC. We found that compared to placebo, LSD impacted local gain and was associated with primarily stronger FC and EC with the notable exception of connections involving occipital and subcortical regions. Moreover, EC correlated with global subjective effects and discriminated experimental conditions with high accuracy (91.11%) highlighting that EC preserved classification accuracy while providing additional mechanistic information pointing towards LSD-induced disturbances of the E/I balance. This result suggests that EC is a promising candidate biomarker to decode or predict subjective effects of LSD in the future.