This double-blind, placebo-controlled, between-subjects study (n=60) investigated the effects of psilocybin (11.9 mg/70kg) on creativity in healthy participants, with respect to acute and persisting changes in convergent and divergent thinking in relation to restructuralization of Default Mode Network (DMN) connectivity. Although subjects felt more insightful under the acute psychedelic state, their ability to generate ideas and associations in a goal-directed manner was impaired. However, 7 days after psilocybin administration, participants generated a higher quantity of novel ideas for uses of an everyday object. Decreased integrity of the DMN under the acute state was the strongest predictor of subjective insightfulness, acute decrease in scores of originality, and a long-term increase in the generation of novel ideas.
“Introduction: Creativity is an essential cognitive ability linked to all areas of our everyday functioning. Thus, ﬁnding a way to enhance it is of broad interest. A large number of anecdotal reports suggest that the consumption of psychedelic drugs can enhance creative thinking; however, scientiﬁc evidence is lacking.
Methods: Following a double-blind, placebo-controlled, parallel-group design, we demonstrated that psilocybin (0.17 mg/kg) induced a time- and construct-related differentiation of effects on creative thinking.
Results: Acutely, psilocybin increased ratings of (spontaneous) creative insights, while decreasing (deliberate) task-based creativity. Seven days after psilocybin, number of novel ideas increased. Furthermore, we utilized an ultrahigh ﬁeld multimodal brain imaging approach, and found that acute and persisting effects were predicted by within- and between-network connectivity of the default mode network.
Discussion: Findings add some support to historical claims that psychedelics can inﬂuence aspects of the creative process, potentially indicating them as a tool to investigate creativity and subsequent underlying neural mechanisms. Trial NL6007; psilocybin as a tool for enhanced cognitive ﬂexibility; https://www.trialregister.nl/trial/6007.”
The same participants (n=60) were also studied by Mason and colleagues (2020) where they studied changes in glutamate in different areas of the brain.
The authors introduce the concept of creativity and build on the distinction between idea generation and evaluation, convergence and divergence, and the neuronal back-and-forth between the Default Mode Network (DMN) and the Frontoparietal Control Network (FPN). And that under psychedelics there is more unconstrained thought and neuronal flexibility. More about this can be found in Girn and colleagues (2020).
The present study looked at the acute effects of psilocybin (11.9mg/70kg) and persistent effects (7 days later). The main tests used were the alternate uses test (AUT, imagining different uses for an object, divergent creativity) and the picture concept test (PCT, used to evaluate both types of creativity). The subjective experience of creativity and altered states (5D-ASC) were also evaluated. Finally, fMRI measures were taken with the following hypothesis:
“… psilocybin would have an acute and persisting increase on outcome measures of [divergent thinking], which would be predicted by within-network [functional connectivity, FC] of the DMN. It was further hypothesized that psilocybin would decrease [convergent thinking] acutely, which would be predicted by alterations in between-network FC of the DMN and FPN.“
During the experience, participants in the psilocybin group performed worse on the convergent creativity part of the PCT. This means that they were worse at selecting the right answer. The effect size found was large (d = 0.85). The same was found for the subscales of the divergent creativity par of the PCT. The participant scores lower on fluency (number of ideas, d = 0.84), and originality (novelty of ideas, d = 0.65). On the AUT, participants were less fluent (fewer ideas) during the experience (d = 0.80).
Seven days later, the effects on divergent creativity were not significantly different from the baseline, on the PCT test. They were still significantly lower on the measure of convergent creativity (d = 0.60). The novelty of the ideas on the AUT test, one week later, was significantly increased (d = 0.52).
The fMRI measured showed a decrease in communication within the DMN, but no significant changes within the FPN and salience network (SN). More communication/functional connectivity was found between the various parts of the brain observed (see figure 2).
The biological predictors of creativity were then worked out through a canonical correlation analysis (a way to find and measure associations between two sets of variables). The authors found that “the strongest predictor of increasingly higher feelings of insight and (positive) changes in longterm novelty, were lower levels of within-network DMN FC acutely” and “the strongest predictor of larger (negative) changes in acute originality were lower levels of within-network posterior DMN FC.” and “the strongest predictor of larger (negative) changes in acute and long-term CT were higher levels of between-network FC between the DMN and the FPN.“
The study found a decrease in divergent thinking/creativity during the psychedelic experience, which ran counter to their hypothesis. The participants themselves did rate the insightfulness of their ideas as higher, prompting the possibility that their evaluation of ideas was less well-calibrated. Still, divergent creativity was higher, as judged by the number of novel ideas (but not the total number), at the seven-day follow-up.
In line with earlier studies (e.g. Kuypers et al., 2016), this study found a decrease in some measures of divergent thinking/creativity. Here the authors also note the importance of having a placebo condition as both groups showed some learning effects on the PCT task.
So, do psychedelics increase creativity? The authors emphasize the difference between subjective and objective creative performance, and between spontaneous and deliberate creativity. The increase in ‘meaningfulness’ induced by psychedelics may be part of the explanation for the former. The latter argues that a goal-directed task (as used here) may not be the most suitable for the psychedelic state which lends it more to exploration, bizarre ideas, and defocused attention.
The decrease in integrity of the DMN and its positive effects on subjective creativity/insightfulness is in line with earlier research (e.g. Girn et al., 2020). The authors also make a connection with our brain whilst dreaming as being very unconstraint.
Psychedelics can be a useful tool for understanding, and possibly enhancing, creativity. And on the other side of the creative coin lies rigid thinking, which is associated with mental health disorders such as depression. The decrease in convergent creativity could be one of the reasons why psychedelic therapy is being found to be effective in combination with therapy.