Neuropsychological effect on long-term Ayahuasca use

Long-term, recurrent religious use of ayahuasca does not produce lasting neuropsychological effects. In a study comparing 12 ayahuasca users from the U.S. branch of União do Vegetal with 13 non-using controls, no differences were found between groups in connectivity of the default mode network (posterior cingulate cortex, angular gyrus, and medial prefrontal cortex) or in mood assessments. A positive association between sleepiness and connectivity in the right medial prefrontal cortex and angular gyrus was observed. The findings suggest that chronic ayahuasca use does not significantly alter brain network connectivity or mood, though larger samples could detect possible subtle effects.

Study at a glance

Abstract

Ayahuasca is a hallucinogenic tea used in religious ritual ceremonies in eastern parts of South America. Ayahuasca is becoming more popular in western countries for therapeutic use for depression, drug addiction, and emotional distress (Domínguez-Clavé et al., 2016). Previous research has explored the effects ayahuasca may have on cognition, neurological functioning, and psychopathology. Although several studies have been done on cognition and psychopathology, few studies have examined the long-term use of neurological functioning. This study focused on neuropsychological effects chronic recurrent religious users of Ayahuasca may develop, using an existing data set. This study analyzed the default mode network (DMN) comprised of the posterior cingulate cortex, angular gyrus, and the medial prefrontal cortex. To assess the DMN functional magnetic resonance images (fMRI) scans were collected. This study included 12 Ayahuasca users from the U.S. branch of União do Vegetal (UDV) and 13 non-Ayahuasca-using controls from Albuquerque Protestant and Catholic churches. No differences were found between groups on connectivity in any region of interest nor in relation to mood assessments. However, the right medial prefrontal cortex and the angular gyrus revealed a positive associated with sleepiness. Possible effects can be assessed on default mode network (DMN) connectivity using a larger sample size. These findings display evidence that long-term use of Ayahuasca does not have essential lasting neuropsychological effects.