Functional imaging studies of acute administration of classic psychedelics, ketamine, and MDMA: Methodological limitations and convergent results

This systematic review (s=51) examines fMRI studies on the acute effects of psychedelics like psilocybin, LSD, and ketamine on the human brain. The review highlights significant methodological inconsistencies across studies, including 54% not meeting contemporary Type I error correction or motion artefact control standards. Despite these limitations, convergent findings indicate that psilocybin and LSD affect the connectivity architecture of the sensorimotor-association cortical axis, while ketamine increases activation in the dorsomedial prefrontal cortex.

Abstract of Functional imaging studies of acute administration of classic psychedelics, ketamine, and MDMA

“Functional magnetic resonance imaging (fMRI) is increasingly used to non-invasively study the acute impact of psychedelics on the human brain. While fMRI is a promising tool for measuring brain function in response to psychedelics, it also has known methodological challenges. We conducted a systematic review of fMRI studies examining acute responses to experimentally administered psychedelics in order to identify convergent findings and characterize heterogeneity in the literature. We reviewed 91 full-text papers; these studies were notable for substantial heterogeneity in design, task, dosage, drug timing, and statistical approach. Data recycling was common, with 51 unique samples across 91 studies. Fifty-seven studies (54%) did not meet contemporary standards for Type I error correction or control of motion artifact. Psilocybin and LSD were consistently reported to moderate the connectivity architecture of the sensorimotor-association cortical axis. Studies also consistently reported that ketamine administration increased activation in the dorsomedial prefrontal cortex. Moving forward, use of best practices such as pre-registration, standardized image processing and statistical testing, and data sharing will be important in this rapidly developing field.”

Authors: Sophia Linguiti, Jacob W. Vogel, Valerie J. Sydnor, Adam Pines, Nick Wellman, Allan Basbaum, Claudia R. Eickhoff, Simon B. Eickhoff, Robert R. Edwards, Bart Larsen, Andrew McKinstry-Wu, J. Cobb Scott, David R. Roalf, Vaishnavi Sharma, Eric C. Strain, Gregory Corder, Robert H. Dworkin & Theodore D. Satterthwaite

Summary of Functional imaging studies of acute administration of classic psychedelics, ketamine, and MDMA: Methodological limitations and convergent results