Impact of psilocybin on cognitive function: A systematic review.
Study Goal
The researchers aimed to evaluate psilocybin's effects on cognitive function and its potential benefits and risks in psychiatric disorders.
Results Summary
Psilocybin showed mixed effects on cognitive function, with no significant changes in global cognition or processing speed in healthy individuals but improvements in sustained attention, working memory, and executive function in treatment-resistant depression (TRD) patients. Emotional processing and empathy were positively modified, while cognitive flexibility and creative cognition initially declined but potentially improved over time.
Population
Healthy volunteers (85% of studies) and patients with treatment-resistant depression (TRD).
Effective Dosage
Macrodoses ranging from 45 μg/kg to 30 mg/70 kg.
Duration
Not specified.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
Psilocybin | no change | global cognitive function | healthy individuals | - | remained mostly unchanged | #1 |
Psilocybin | no change | processing speed | healthy individuals | - | remained mostly unchanged | #2 |
Psilocybin | increase | sustained attention | patients with treatment-resistant depression (TRD) | - | improvements | #3 |
Psilocybin | increase | working memory | patients with treatment-resistant depression (TRD) | - | improvements | #4 |
Psilocybin | increase | executive function | patients with treatment-resistant depression (TRD) | - | improvements | #5 |
Psilocybin | increase | emotional processing | TRD patients | - | positively modified | #6 |
Psilocybin | increase | emotional empathy | - | - | enhance | #7 |
Psilocybin | no change | cognitive empathy | - | - | without significantly altering | #8 |
Psilocybin | no change | social cognition | - | - | without significantly altering | #9 |
Psilocybin | decrease | cognitive flexibility | - | - | initially decline | #10 |
Psilocybin | decrease | creative cognition | - | - | initially decline | #11 |
Psilocybin | increase | cognitive flexibility | - | - | potentially improve over time | #12 |
Psilocybin | increase | creative cognition | - | - | potentially improve over time | #13 |
Psilocybin | increase | specific memory types such as semantic associations | - | - | showed promise in improving | #14 |
Psilocybin | increase | associative learning | - | - | showed promise in improving | #15 |
Psilocybin | no change | episodic memory | - | - | less pronounced | #16 |
Psilocybin | no change | verbal memory | - | - | less pronounced | #17 |
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.