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Matthew X. Lowe

5 papers in the library · 108 citations · publishing 2023-2025

Papers

Naturalistic psilocybin use is associated with persisting improvements in mental health and wellbeing: results from a prospective, longitudinal survey

Frontiers in Psychiatry September 19, 2023 Hillary Jackson, Sara So, Abigail Yaffe et al. 87 citations

A large prospective survey of adults planning to take psilocybin outside clinical settings found that, on average, participants reported lasting reductions in anxiety, depression, and alcohol misuse, along with improvements in cognitive flexibility, emotion regulation, spiritual wellbeing, and extraversion, and decreases in neuroticism and burnout after use. However, a minority reported persisting negative effects: 11% at 2–4 weeks and 7% at 2–3 months after use, including mood fluctuations and depressive symptoms. The study included 2,833 respondents at baseline, 1,182 at 2–4 weeks, and 657 at 2–3 months post-use. Participants were primarily college-educated White men in the United States, mean age 40, who used dried psilocybin mushrooms (mean dose 3.1 grams) for self-exploration.

Shame, Guilt and Psychedelic Experience: Results from a Prospective, Longitudinal Survey of Real-World Psilocybin Use

Journal of Psychoactive Drugs February 7, 2025 Amy Lehrner, Heather Jackson, David S. Mathai et al. 11 citations

Among 679 adults using psilocybin in naturalistic settings, 68.2% reported acute feelings of shame or guilt during the experience, which were difficult to predict. The ability to constructively work through these feelings predicted wellbeing 2-4 weeks later. On average, psilocybin produced a small but significant decrease in trait shame maintained 2-3 months after use (Cohen's dz = 0.37), though trait shame increased in 29.8% of participants. The activation of self-conscious emotions with psychedelics warrants further attention as a challenging experience subcategory relevant to psychological outcomes, potentially creating a unique learning condition for shame-related memory reconsolidation.

A lexicon for psychedelic research and treatment

Drug Science Policy and Law September 1, 2025 David Nutt, David Erritzøe, Anne Katrin Schlag et al. 9 citations

The field of psychedelic research lacks standardized terminology for clinical development, dosing, safety monitoring, and regulatory classification. A comprehensive framework is proposed that classifies psychedelics by pharmacology (serotonergic, glutamatergic, kappaergic, GABAergic, and atypical), introduces dose-dependent categories (microdose, minidose, mididose, macrodose), and standardizes terms like “short-acting” with specific pharmacokinetic parameters. Safety considerations include cardiovascular and psychological effects, with risk mitigation protocols for higher-risk compounds like ibogaine. A three-phase treatment model—preparation, dosing, and integration—is recommended as a minimum standard. The lack of comparative research on psychotherapy modalities is identified as a critical gap.

Naturalistic Psilocybin Use Increases Mind Perception but not Atheist-Believer status: A Prospective Longitudinal Study

June 9, 2023 Sandeep M. Nayak, Sydney White, Samantha Hilbert et al. 1 citation preprint

A longitudinal study of 657 people planning a psychedelic experience measured changes in beliefs about mind perception, metaphysical positions, and Atheist-Believer status before and after the experience. Replicating prior work, participants showed increased mind perception for living and non-living targets such as plants and animals. However, there was little to no change in metaphysical beliefs like dualism or in Atheist-Believer status. These results contrast with cross-sectional studies suggesting psychedelics alter non-naturalistic beliefs or religious identity, but they support the idea that psychedelics specifically affect how people perceive minds in various entities.

Shame, guilt and psychedelic experience: Results from a prospective, longitudinal survey of real-world psilocybin use

October 14, 2023 David S. Mathai, Daniel E. Roberts, Sandeep M. Nayak et al. preprint

A longitudinal study of 679 adults planning to use psilocybin in naturalistic settings found that while most users (89.7%) described the experience as positive, acute feelings of shame or guilt were commonly reported (68.2% of users) and difficult to predict. The ability to constructively work through these feelings predicted wellbeing 2-4 weeks after use. Psilocybin produced a small but significant average decrease in trait shame that lasted 2-3 months, but trait shame increased in a notable minority (29.8%) of participants. The activation of shame-related experiences with psychedelics may pose a unique learning condition for both therapeutic and detrimental forms of memory reconsolidation.