Speaker Bio
Moritz Spangemacher is a physician and PhD candidate at the Central Institute of Mental Health in Mannheim. He works in the department of molecular neuroimaging, led by Prof. Gerhard Gründer. His focus lies in the treatment of treatment-resistant depression and the research on psychotropic drugs. He works as a therapist in the EPisoDE study, which is a Phase-II-study that investigates the safety and efficacy of psilocybin in treatment-resistant depression. He is also partly responsible for the fMRI part of the study that explores the underlying mechanisms of the psilocybin effect. Furthermore, he investigates potential blood biomarkers for treatment response in the course of ketamine treatment.
ICPR 2024 Abstract
Absence of Psychedelic Effects: A Systematic Literature Review and Explorative IPD Analysis
Theoretical Background and Rationale: Prior work has shown that the acute psychoactive effects of classic psychedelics seem to have an essential impact on the therapeutic efficacy. Interestingly enough, there have been cases of subjects who did not experience any acute, subjective drug effects. Unfortunately, these cases are rarely discussed in detail. Anecdotal evidence of subjective effects failing to appear has already been described over decades even when high dosages were administered.
Research Question and Hypothesis: Our aim is to find similar cases lacking acute psychedelic effects in a systematic literature review. To our knowledge, this would be the first description of this special cohort.
Methods and Analysis: An electronic databases search for relevant articles (Medline via PubMed) was systematically performed in April 2023. For methodological reasons, only studies from 1994 to 2023 and only studies in humans were included. Mini- or microdosing studies were not included.
Main Findings: 288 relevant studies were extracted. So far, only five subjects could be identified that showed no subjective effects (four patients took 20 – 25 mg of psilocybin; one patient took multiple doses of LSD up to 200 μg). However, most cases were not presented individually and in most of the studies, only mean effects of psychometric scales of subjective effects were given. We will contact the various research groups to ask for details and similar cases of subjects.
Conclusion: This previously undescribed subgroup of individuals may provide a new perspective and challenge to existing concepts in psychedelic therapy and research.