Cannabis has the effect of slightly increasing alpha-wave activity in the brain, and increasing blood flow into the right hemisphere, which is associated with holistic, nonlinear thought. Alpha waves, and right-brain thinking, are generally associated with meditative and relaxed states of consciousness, which are, in turn, often associated with creativity. 

Does Cannabis Boost Creativity? | Santa Cruz Patch

From Charles Baudelaire to George Carlin, Shakespeare to Carl Sagan, Louis Armstrong to Paul McCartney, Norman Mailer to Jack Nicholson, the list of accomplished creative people who have claimed a positive influence from their use of cannabis is truly impressive.

I’ve personally spoken with many accomplished people who made claims about how essential cannabis was for their creative process. For example, when I interviewed the late comedian George Carlin, he told me:

“Pot…changed my thinking. It fostered offbeat thinking…Then it changed my comedy….I became more myself. The comedy became more personal, therefore more political, and therefore more successful…So, suddenly, I also became materially successful. People started buying albums. I had four Gold albums in a row.”

[…] Anecdotes about cannabis and creativity abound, but what does the scientific research say?

The Beckley Foundation—a nonprofit organization in England that supports pioneering, multidisciplinary research with cannabis and psychedelic drugs—is presently funding a two-part study on cannabis and creativity, that is being conducted by neuroscience researchers Valerie Curran and Celia Morgan at the University College London.

Curran and Morgan are currently testing the effects of cannabis use on creativity in 400 subjects, and are then using neuroimaging technology to observe the neurobiological changes in the participants that are associated with creativity, while they are under the influence of cannabis. 

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