Frontiers in Pharmacology
September 16, 2021
Lukas A Basedow, Thomas Riemer, Simon Reiche et al.
16 citations
Repeated use of serotonergic psychedelics such as LSD, ayahuasca, and peyote is associated with distinct neuropsychological profiles rather than a uniform pattern of impairment. A systematic review of 13 studies (539 participants) found that LSD users performed worse on executive-functioning tasks, ayahuasca users showed better performance on the Stroop incongruent task, and peyote users showed no differences across domains. However, methodological quality varied widely, and most studies failed to fully control for confounding factors like other substance use. The evidence suggests that different psychedelics may have different long-term cognitive consequences.
Scientific Reports
June 26, 2024
Lukas A Basedow, Tomislav Majić, Nicklas Jakob Hafiz et al.
13 citations
A systematic review and meta-analysis examined how psychedelics and MDMA affect cognitive performance during acute drug effects and the sub-acute (afterglow) window. Acute psychedelic use impairs attention and executive function, while MDMA primarily impairs memory, leaving executive functions and attention unaffected. During the sub-acute period (at least 24 hours after acute effects subside), executive functioning and creativity may be increased following psychedelics, but no such effects were observed for MDMA. These findings can inform harm reduction recommendations for recreational use and support differential therapeutic approaches for psychedelics and MDMA.
Journal of Psychopharmacology
March 31, 2025
Tomislav Majić, Timo Torsten Schmidt, Anna Gröticke et al.
4 citations
A new questionnaire called the Afterglow Inventory (AGI) reliably measures pleasant psychological effects that can occur days after a psychedelic experience, such as with psilocybin or LSD. The AGI captures five distinct dimensions: vitality, transpersonal aspects, inspiration/creativity, interpersonal relationships, and relationship to nature. In an international online survey of 1,323 people who had recently used a psychedelic and 157 controls, the AGI successfully distinguished between the two groups. Stronger and more positive acute psychedelic experiences were associated with higher afterglow scores. This tool may help researchers understand how short-term afterglow effects connect to longer-term therapeutic outcomes.
Scientific Reports
December 31, 2024
Georg Leistenschneider, Tomislav Majić, Simon Reiche et al.
3 citations
Classic psychedelics like LSD and psilocybin show promise for treating psychiatric disorders but can occasionally cause lasting psychological harm, including Hallucinogen Persisting Perception Disorder (HPPD), a rare condition with enduring perceptual symptoms. This study examined the neuropsychological profiles of eight individuals with HPPD using a comprehensive test battery, comparing their performance against normative data and two matched control groups (with and without prior psychedelic use). Some participants with HPPD scored below average on tests of visual memory and executive function. Statistically adjusted comparisons found no significant differences between groups, though unadjusted analyses hinted at impaired executive functions in HPPD patients. These preliminary findings highlight the need for more focused research on the neuropsychological aspects of HPPD.
October 22, 2024
Tomislav Majić, Timo Torsten Schmidt, Anna Gröticke et al.
1 citation
preprint
A new questionnaire called the Afterglow Inventory (AGI) was developed and validated to measure the pleasant, temporary psychological effects that sometimes follow the acute phase of a psychedelic experience. An international online survey of 1,323 people who had taken a psychedelic and 157 who had taken a non-psychedelic substance in the past four weeks identified five key factors: vitality, transpersonal aspects, inspiration/creativity, interpersonal relationships, and relationship to nature. The 24-item AGI successfully distinguished psychedelic users from controls, and its overall score was positively correlated with the intensity and positive valence of the acute effects. The AGI may help researchers better understand how acute, subacute, and long-term effects of psychedelics relate to each other.
medRxiv Preprint Server
May 23, 2026
Lisa Maria Jöbstl, Bente Lubahn, Ebru Kaya et al.
preprint
A subset of individuals who use classic psychedelics outside clinical settings reports persisting adverse effects, including hallucinogen persisting perception disorder, depersonalization/derealization disorder, anxiety, and depression. Despite growing non-clinical use, few medical services are equipped to address these complications. The authors highlight a delay in attention to these persisting adverse effects relative to enthusiasm for therapeutic potential.