EEG Gamma Coherence and Other Correlates of Subjective Reports During Ayahuasca Experiences
Journal of Psychoactive Drugs – June 01, 2005
Source: OpenAlex
Summary
Increased global EEG coherence in the 36-44 Hz and 50-64 Hz frequency bands was observed during ayahuasca experiences, indicating intense synesthesia among two participants in a Brazilian jungle. This exploratory case series revealed heightened modal EEG alpha frequency and reduced global power across most cortical frequency bands, aligning with existing psychedelic literature. Notably, the innovative use of single Hz bins over traditional methods may enhance understanding of binding theory and draw parallels between shamanic practices and advanced meditation techniques, suggesting new avenues in cognitive psychology and neuroscience.
Abstract
The current study examined QEEG power and coherence of ayahuasca experiences with two experienced participants in a Brazilian jungle setting. An exploratory case series design was adopted for naturalistic field research. EEGs recorded during visual imagery was compared to eyes-closed baselines. The most important findings were increases in global EEG coherence in the 36-44 Hz and 50-64 Hz frequency bands for both subjects. Widely distributed cortical hyper-coherence seems reasonable given the intense synesthesia during ayahuasca experiences. Other findings include increased modal EEG alpha frequency and global power decreases across the cortex in most frequency bands, which concur with the EEG of psychedelics literature. Exploratory analysis revealed the usefulness of analyzing single Hz bins over the standard wide-band analysis. The discovery-oriented naturalistic approach developed for this study resulted in potentially important findings. We believe that finding increases in global gamma coherence during peak psychedelic experiences might contribute to the discussion of binding theory. Also, in light of recent research with gamma coherence during advanced meditative conditions, our findings might further the comparison of shamanic psychedelic practices with meditation.