LSD and creativity: Increased novelty and symbolic thinking, decreased utility and convergent thinking.

Background: Controversy surrounds psychedelics and their potential to boost creativity. To date, psychedelic studies lack a uniform conceptualization of creativity and methodologically rigorous designs.
Aims: This study aimed at addressing previous issues by examining the effects of lysergic acid diethylamide (LSD) on creativity using multimodal tasks and multidimensional approaches.
Methods: In a randomized, double-blind, placebo-controlled, crossover study, 24 healthy volunteers received 50 μg of LSD or inactive placebo. Near drug peak, a creativity task battery was applied, including pattern meaning task (PMT), alternate uses task (AUT), picture concept task (PCT), creative metaphors task (MET) and figural creativity task (FIG). Creativity was assessed by scoring creativity criteria (novelty, utility, surprise), calculating divergent thinking (fluency, originality, flexibility, elaboration) and convergent thinking, computing semantic distances (semantic spread, semantic steps) and searching for data-driven special features.
Results: LSD, compared to placebo, changed several creativity measurements pointing to three overall LSD-induced phenomena: (1) 'pattern break', reflected by increased novelty, surprise, originality and semantic distances; (2) decreased 'organization', reflected by decreased utility, convergent thinking and, marginally, elaboration; and (3) 'meaning', reflected by increased symbolic thinking and ambiguity in the data-driven results.
Conclusion: LSD changed creativity across modalities and measurement approaches. Three phenomena of pattern break, disorganization and meaning seemed to fundamentally influence creative cognition and behaviour pointing to a shift of cognitive resources 'away from normal' and 'towards the new'. LSD-induced symbolic thinking might provide a tool to support treatment efficiency in psychedelic-assisted therapy.