There could be scientific evidence that psychedelic drugs give people a heightened sense of consciousness.  Researchers gave people LSD, ketamine and psilocybin and measured their brain activity.  Their brains were more active with more complex signals, particularly in the part of the brain linked with perception.  

Compared to people who are awake and people who are asleep, the brain activity indicates a higher level of consciousness than someone sober and awake.  The findings are published in the journal Scientific Reports.

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