Effects of the Amazonian Psychoactive BeverageAyahuascaon Binocular Rivalry: Interhemispheric Switching or Interhemispheric Fusion?
Ede Frecska, Keith D. White, Luis E. Luna
Journal of Psychoactive Drugs September 1, 2003 DOI: 10.1080/02791072.2003.10400019 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Ceremonial participants who ingested ayahuasca |
| Intervention | Ayahuasca |
| Topics | Ayahuasca |
| Keywords | Binocular rivalry Hallucinogen Consciousness Perception Audiology Cognitive psychology |
| Citations | 12 |
| Key findings | Ayahuasca ingestion decreased rivalry alternation rates, increased percept length, and produced evidence of phenomenal fusion. |
Abstract
An early theoretical analysis supposed changes in hemispheric integration as the basis of altered state of consciousness induced by psychoactive drugs. Brain imaging studies revealed right cortical activation after administration of hallucinogens. Recent studies on binocular rivalry suggest that interhemispheric switching is the neural substrate of the perceptual oscillations observed during dichoptic stimulus presentation. The current study tested perceptual alternation in ceremonial participants, who ingested the South American hallucinogenic beverage ayahuasca, to examine the claim that there might be changes in interhemispheric function under the influence of hallucinogens. Ingestion of ayahuasca resulted in a decrease of rivalry alternation rates, increased length of one percept and there was evidence of phenomenal fusion. The findings are in line with results of brain activation studies and support the concept of interhemispheric fusion in altered states of consciousness.