Psychedelics and Creativity: a Review of the Quantitative Literature

This review (2015, pre-print) of the psychedelics literature on creativity argues that creativity is too elusive/inconsistent a measure that is confounded by other changes.

Abstract

After a 40-year hiatus, the question of whether psychedelics can increase creativity is being asked with renewed vigor. This article critically reviews the conceptual issues of studying psychedelic induced creativity by summarizing the limited evidence on the question and suggesting two broader frameworks. There are two important challenges to researchers on this topic. One is to separate creativity from other effects of the drug that may be mistaken for creativity. The second is to develop operational measures to quantify it. This article reviews the major studies assessing creativity (or related constructs) induced by psychedelics, including a reanalysis of raw data from one study. Results are modest and inconclusive but are consistent with reports that psychedelics give rise to unusual or novel thoughts. Given the lack of robust changes in creativity measures, I suggest creativity may be too specific of a construct to accurately and fully characterize the putatively beneficial cognitive changes that psychedelic users report. Feelings of creativity may be an inconsistent result of a more general effect of these drugs, such as alterations in [the] availability of mental representations or changes in Bayesian inference. Ultimately, creativity may not be a sufficiently creative construct to capture the beneficial effects of psychedelics.

Author: Matthew J. Baggott

Notes

“… psychedelics give rise to unusual or novel thoughts”

The two broader theories/underlying mechanisms he proposes are:

  • “released representations as a potential general mechanism of psychedelic-induced changes in creativity
    • psychedelics impair the ability of the thalamus to selectively gate information, which leads to continued inappropriate activation of representations and overprocessing of sensory and interoceptive information
  • alterations of Bayesian inference (also see REBUS and the anarchic brain)
    • hierarchical Bayesian ones, that regard the brain as attempting to predict regularities in the environment in order to successfully interact with it”

Summary

Abstract

After a 40-year hiatus, researchers are asking whether psychedelics can increase creativity. The results are modest and inconclusive, but suggest that creativity may be too specific of a construct to accurately characterize the putatively beneficial cognitive changes that psychedelic users report.

Introduction

Psychedelics are often said to increase creativity, but this claim is complex to evaluate because creativity itself is hard to measure. Recently, scientists have begun to examine the literature on how psychedelics might act as cognitive enhancers and improve creativity.

Psychedelics have been associated with creativity in a broad range of nonscientific publications, including Nobel laureate Kerry Mullis and author Ken Kesey, as well as the creation of innovative albums and movies like Easy Rider and Robert Crumb’s work.

There are reasons to be skeptical about the perceived effects of psychedelics on creativity. Objective tests consistently find hallucinogen-induced impairments in other cognitive domains, and the erroneous belief that the impaired abilities are enhanced is often accompanied by subjective feelings of improvement.

This publication reviews the literature on the effects of psychedelics on creativity and discusses two broader conceptualizations of psychedelic effects that may clarify creativity-related changes.

Acute effects of psychedelics potentially related to creativity

Psychedelics can have a range of inconsistent effects on cognition, mood, and perception, which may be related to creativity. These effects include perceptual changes, time-distortions, altered and frequently labile mood, feelings of depersonalization and derealization, and feelings of insight and altered meaning.

Feelings of insight and altered significance are recognized as a common acute effect of psychedelics, and are included in many self-report questionnaires developed to measure the effects of these drugs.

Psychedelics are often said to change the dynamics of thought, with participants reporting a tendency to see “multiple viewpoints of a problem in very rapid succession” and a decrease in the stability of points of view. This may be related to creativity.

Psychedelics increase use of unusual language, which is less concrete and more abstract than seen in thought-disordered schizophrenia. This language is often image-based.

Traditional approaches to studying creativity

There are many proposed definitions for creativity, and different tasks can be used to study it. The most common tasks are influenced by Guilford and Mednick, and the results of these studies are summarized in Table 1.

Three main categories of tasks can be found in these tests: remote associations, perception and visual imagery, and creative production.

This task-based approach to measuring creativity has several limitations, including the possibility that it may miss relevant drug-induced changes, and the possibility that changes on specific tasks may be driven or masked by nonspecific drug effects, such as altered motivation.

Five studies of psychedelics and creativity

With one recent and important exception, all research on psychedelics and creativity was conducted between 1962 and 1968. These studies represent human psychedelic research at a peak in hands-on practical experience.

Studies 1 and 2 sought to find lasting effects of LSD exposure in healthy normal volunteers, including changes in creativity. However, objective measures did not support any lasting increase in creativity.

McGlothlin, Cohen, & McGlothlin (1964) tested fifteen psychedelic-nave RAND Corporation employees before and one week after administration of 200 g LSD. They found no significant changes in divergent thinking.

In a second study, 24 psychedelic-nave graduate students reported increased enjoyment of art and increased time spent in museums and musical events after a series of three administrations of 200 g LSD, a high dose. However, standardized art tests failed to show significant changes in aesthetic sensitivity.

MacLean et al (2011) pooled data from two studies that used high-dose experimental psilocybin and found increases in the openness dimension of personality associated with study participation.

Two studies were conducted: one with psilocybin and one with methylphenidate. In the second study, participants received four doses of psilocybin in ascending or descending order over four sessions, with a fifth placebo session quasi-randomly inserted in the sequence.

The authors found that openness changed from pretest to post-session-one in all 52 participants, and that this change was psychedelic-linked and not a more general effect of the unusual study.

The participants were unusual, because they were naive to psychedelics and had some preexisting spiritual practice. Their mean openness was 64, and their mean neuroticism was nearly 1 SD below the population normal.

Several recent reports exist of drug-related mystical experiences triggered by other drugs and in other settings, yet there are no published reports quantifying personality changes after these experiences.

Study 4: LSD and creativity in graduate students

Zegans, Pollard, & Brown (1967) administered 0.5 g/kg of LSD to 20 psychedelic-nave male graduate students and controlled expectation by reading a short statement about the drug’s effects that carefully omitted the possibility of “regressive experiences”.

Zegans et al. found that participants who had taken LSD had a greater number of unusual word associations on the Rapaport Word Association Test compared to controls, but that their performance in the Gottschald Figure-Perception task was also impaired.

Study 5: Institute of Psychedelic Research report on psychedelics and creativity in professionals

Harman, McKim, Fadiman and colleagues studied the effects of mescaline on creativity, using objective testing and qualitative assessment of participants’ attempts to solve professional problems.

This report differs from other studies in that it attempted to maximize creativity, and also included participants with prior experience with psychedelics. Additionally, participants were advised that they would be able to concentrate on the assigned tasks with ease and would be able to work more effectively than usual.

Participants took 200 mg of mescaline, completed a one-hour battery of cognitive tasks, and then worked on a self-chosen problem. About half felt the experience enhanced their abilities to solve professional problems, and about 20% reported they were unable to concentrate on their chosen project.

Although self-report measures were not a primary focus of the study, 16 participants reported continuing benefit in 6 categories (ability to solve problems, ability to relate effectively to others, attitude toward job, productivity, ability to communicate, response to pressure).

Researchers collected data from 25 different males and 8 females and reported significant improvements in all three cognitive tasks. The data were reanalyzed over forty years later and showed that the qualitative self-chosen problem-solving task was the main focus of the research.

I replicated the analyses of Harman et al. using their data, and found that the Witkin’s Embedded Figures and Purdue Creativity tasks showed significant improvements, while the Miller Object Visualization task did not. In addition, there were significant gender differences in scores in both tasks with female participants.

The Harman et al. report has three methodological limitations: the absence of a placebo control, inconsistent administration of tests, and the apparent co-administration of other pharmacological agents.

The inconsistent pattern of test administration suggests a potential confound. The number of tests taken was correlated with change in performance in the Miller Object Visualization task, but not with the Purdue Creativity and Witkin’s Embedded Figures tests.

The preliminary report of the study indicates that participants received methamphetamine and chlordiazepoxide along with the mescaline. This confounding factor has not been noted by subsequent commentators.

The study by Fadiman and colleagues uses polypharmacy, which limits conclusions about psychedelics per se. Some or all of the objective measures employed in the study may be sensitive to benzodiazepines and stimulants, and combining these drugs with psychedelics may improve creativity.

The results of these studies are inconsistent with reports that psychedelics cause a change in cognition that gives rise to unusual or novel thoughts, yet the quantitative measures do not seem to have captured these changes.

This study failed to measure the effects of psychedelics on creativity. This could be because the quantitative tasks failed to tap into the specific domains improved by psychedelics, or because participants experienced dysphoric effects. The study may have failed to engage participants because the task used to measure improvement was not professionally relevant, and participants were not blinded to the researchers’ attempt to improve performance.

The feelings of creativity that psychedelic users report are a variable subset of the changes individuals attribute to psychedelics. Thus, it may be useful to study psychedelic users to develop a typology of the perceived benefits and harms.

Psychedelics are thought to improve creative performance by facilitating release of stored representations or memories, or by impairing the gating of representations. However, these effects may not necessarily improve accurate evaluation of these ideas.

In the influential Cattell-Horn-Carroll model of cognitive ability, psychedelic effects are primarily in Factor Glr (Long-term Storage and Retrieval), which includes the ability to retrieve or reconstruct stored information through association.

Researchers have implicitly assessed changes using reaction time measures in a semantic priming paradigm, which is conceptually similar to Mednick’s Remote Associates Test. Indirect semantic priming refers to facilitation of response when less closely related word pairs are used, which are usually related via a mediating word.

Spitzer et al. (1996) found that 0.2 mg/kg psilocybin increased indirect semantic priming, and Gouzoulis-Mayfrank et al. (1998) found that 0.2 mg/kg psilocybin increased indirect semantic priming but not direct semantic priming.

A hierarchical Bayesian framework can explain some aspects of psychedelic effects on cognition, but not the broader phenomenology of psychedelics.

In hierarchical Bayesian theories, brain systems are arranged in hierarchies, and each level attempts to predict input from a lower level using prior beliefs that have been obtained by top-down feedback from a higher level area. Mismatches indicate that the existing interpretation has not fully accounted for the input.

Psychedelics might impair Bayesian inference in a number of ways, including by decreasing the reliability of bottom-up sensory signals while preserving the top-down signal that can add structure to this noisy bottom-up signal.

A Bayesian perspective suggests that creativity may be caused by aberrant bottom-up signals, which indicate that further, higher-level processing is needed to understand the phenomenon at hand. This hypothesis is reminiscent of the large literature in psychology showing that disagreement can improve decision-making.

Filtering failures induced by psychedelics can be reinterpreted within a Bayesian framework, where filtered-out information is that which is fully predicted. This sense of unexpectedness can be related to the qualitative feelings of altered meaning reported by psychedelic users.

Conclusions

Psychedelics have unique and powerful effects, yet controlled research on psychedelics and creativity is lacking. Qualitative research may provide more insight into how individuals use psychedelics to enhance their creativity or gain other perceived benefits.

Legends for Table and Figures

Males perform better than females in the Miller Object Visualization task, Witkin’s Embedded Figures task, Purdue Creativity task, and the change in Miller Object Visualization score is significantly predicted by number of tests taken.

Reanalysis of quantitative test results from Harman et al.

Harman and colleagues used chi-square goodness-of-fit tests to analyze their data, but it proved difficult to replicate the original analyses. Additionally, gender differences were detected in both tasks that included females.

Miller Object Visualization scores were plotted in Figure 2a with higher scores indicating better performance. However, the reanalysis did not replicate the original findings and a chi-squared test did not achieve significance.

A paired two-sided t-test did not confirm an effect of measurement time, but a visual inspection of the data strongly suggested a main effect of gender. A linear model with gender and measurement time and a gender*time interaction term predicted performance.

The time needed to complete Witkin’s Embedded Figures task decreased by 168 sec (95%CI: 68 – 269 sec, t = 3.62, df = 13), and participants improved between the first and second administration of the task, consistent with a drug effect.

The Purdue Creativity test showed significant improvements in fluency scores, but the total score did not. The reanalysis failed to confirm the improvement using the originally reported categorical analysis, but the trend in fluency scores was in the expected direction.

Inclusion of either both of participant 207’s sessions or only his first session resulted in significant results (t = -2.33, df = 17, p = 0.03; first session only: t = -2.27, df = 16, p = 0.04).

I have reanalyzed the Harman et al. report and found significant gender differences in scores in both tasks in which there were female participants. The gender differences are probably not due to the females weighing less and therefore receiving higher drug doses.

Study details

Topics studied
Creativity

Study characteristics
Literature Review Commentary

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