Fig. 1: Connectogram views of differences in functional (FC) and effective connectivity (EC) between LSD and placebo conditions.

A Across-participant average FC in the LSD condition. B Across-participant average FC in the placebo condition. C Across-participant t-statistic values of difference between FC in LSD and placebo conditions. D Feature importance estimates for the FC classification model. See ’Statistical analysis’ for a detailed definition of feature importance. E Across-participant average EC in the LSD condition. F Across-participant average EC in the placebo condition. G Across-participant t-statistic values of difference between EC in LSD and placebo conditions. H Feature importance estimates for the EC classification model. Differences in magnitudes of connectivity are indicated in each connectogram by both line width and opacity. In (C) (FC) and (G) (EC), orange and blue lines indicate stronger and weaker connectivity, respectively, in connectivity in the LSD condition. Note that for (E)–(H), both directional EC values between each pair of regions have been averaged for display. To maintain visibility, only the top 250 connections have been displayed. PFr Prefrontal cortex. Fr Frontal cortex. Ins Insular cortex. Tem Temporal cortex. Par Parietal cortex. Occ Occipital cortex. SbC Subcortical regions. CeB Cerebellum. Ver Vermis. Bstem Brainstem.