Impact of psilocybin on cognitive function: A systematic review
Shakila Meshkat, Fatemeh Gholaminezhad, Eric Vermetten, Yanbo Zhang, Lisa Burback, Olga Winkler, Rakesh Jetly, Venkat Bhat, Triana Juliana Tello‐gerez, Benjamin T. Dunkley, Amy C. Reichelt, David Erritzøe, Andrew J. Greenshaw, Leah M. Mayo
Psychiatry and Clinical Neurosciences October 1, 2024 DOI: 10.1111/pcn.13741 via OpenAlex
Summary
AI-generated from the abstractA systematic review of 20 studies with 2,959 participants found that psilocybin's effects on cognitive function are mixed. Global cognitive function and processing speed remained mostly unchanged in healthy individuals, while improvements in sustained attention, working memory, and executive function were reported in patients with treatment-resistant depression. Emotional processing and empathy were positively modified, especially in these patients, but cognitive empathy and social cognition were not significantly altered. Cognitive flexibility and creative cognition initially declined but could improve over time. Psilocybin improved semantic associations and associative learning, but effects on episodic and verbal memory were less pronounced than with other cognitive enhancers.
Study at a glance
| Characteristics | Systematic review Peer reviewed |
|---|---|
| Sample size | 2,959 |
| Population | Healthy volunteers and patients with treatment-resistant depression |
| Intervention | Psilocybin |
| Dose | 45 μg/kg to 30 mg/70 kg |
| Topics | Psilocybin |
| Keywords | Cognition Empathy Cognitive flexibility Cognitive psychology |
| Citations | 24 |
| Key finding | Psilocybin's effects on cognitive function are mixed, with improvements in some domains like sustained attention, working memory, executive function, and emotional processing, particularly in patients with treatment-resistant depression, while global cognitive function and processing speed remain mostly unchanged in healthy individuals. |
Abstract
Psilocybin is a classic psychedelic with demonstrated preliminary clinical efficacy in a range of psychiatric disorders. Evaluating the impact of psilocybin on cognitive function is essential to unravel its potential benefits and risks. In this systematic review, we assessed psilocybin's effect on cognitive function through a comprehensive search of electronic databases from inception to January 2024, identifying 20 articles involving 2,959 participants. While 85% of studies were conducted in healthy volunteers, most of these studies (85%) used macrodoses, ranging from 45 μg/kg to 30 mg/70 kg. Various cognitive aspects were evaluated and yielded mixed results. Global cognitive function, and processing speed remained mostly unchanged in healthy individuals; However, a limited number of studies reported improvements in certain areas such as sustained attention, working memory, and executive function especially in patients with treatment‐resistant depression (TRD). Emotional processing was positively modified, particularly in TRD patients. Psilocybin was observed to enhance emotional empathy without significantly altering cognitive empathy and social cognition. Cognitive flexibility and creative cognition were noted to initially decline but could potentially improve over time. Additionally, with respect to learning and memory skills, psilocybin showed promise in improving specific memory types such as semantic associations and associative learning, while its effects on episodic and verbal memory have been less pronounced compared to other cognitive enhancers. The observed mixed findings underscore the complexity of psilocybin's cognitive influence. Further research is essential to provide a clearer understanding of psilocybin's impact on cognitive domains and to guide the development of safe and effective interventions.