Monday, October 31, 2011

This is your brain on ayahuasca. Or is it?

Reporting for New Scientist, Arran Frood brings us the results of a Brazilian study that looked at the brain activity of frequent users of ayahuasca, a tea prepared from a jungle vine and traditionally used by shamans. Researchers scanned the brains of subjects as they looked at images of people or animals, as they closed their eyes and imagined the object, and as they closed their eyes and imagined the objects after a dose of ayahuasca. The results?
...researchers found that neural activity in the primary visual cortex dropped off when volunteers imagined seeing the image rather than actually viewing it.

But when the team then gave the volunteers a dose of ayahuasca and repeated the experiment, they found that the level of activity in the primary visual cortex was virtually indistinguishable when the volunteers were really viewing an image and when they were imagining it. This means visions seen have a real, neurological basis, says de Araujo – they are not made up or imagined.

Evidently, the pharmacology of ayahuasca resembles that of some more conventional drugs for treating addiction, depression, and post-traumatic stress disorder. Perhaps this Amazon concoction will join the ranks of LSD in tomorrow's medicine cabinet.
To read the entire story, see Drug hallucinations look real in the brain