Emotion regulation effects of Ayahuasca in experienced subjects during implicit aversive stimulation: An fMRI study

• Published in: Journal of ethnopharmacology 2024-02, Vol.320, p.117430-117430, Article 117430
• Main Authors: Arruda Sanchez, Tiago, Ramos, Lucas Rego, Araujo, Felipe, Schenberg, Eduardo Ekman, Yonamine, Mauricio, Lobo, Isabela, de Araujo, Draulio Barros, Luna, Luis Eduardo
• Format: Article
• Language: English
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2023.117430

ETHNOPHARMACOLOGICAL RELEVANCEAyahuasca is a beverage used in Amazonian traditional medicine and it has been part of the human experience for millennia as well as other different psychoactive plants. Although Ayahuasca has been proposed as potentially therapeutic as an anxiolytic and antidepressant, whilst no studies have been carried out so far investigating their direct effect on brain emotional processing.AIM OF THE STUDYThis study aimed to measure the emotional acute effect of Ayahuasca on brain response to implicit aversive stimulation using a face recognition task in functional magnetic resonance imaging (fMRI).MATERIALS AND METHODSNineteen male experienced Ayahuasca users participated in this study in two fMRI sessions before and after 50 min of the Ayahuasca ingestion. Subjects were presented with pictures of neutral (A) and aversive (B) (fearful or disgusted) faces from the Pictures of Facial Affect Series. Subjects were instructed to identify the gender of the faces (gender discrimination task) while the emotional content was implicit. Subjective mood states were also evaluated before Ayahuasca intake and after the second fMRI session, using a visual analogue mood scale (VAMS).RESULTSDuring the aversive stimuli, the activity in the bilateral amygdala was attenuated by Ayahuasca (qFDR