This is a shortening and paraphrasing of a recent article at Discovery.com - please do read the original.
Under the supervision of Dr. David Nutt, professor of neuropsychopharmacology at Imperial College, London, fifteen brave souls lay still for an hour in a brain scanner while undergoing a full-blown mushroom trip.
It wasn't a traditional trip. Dr. Nutt administered the psilocybin - the active ingredient - intravenously. It took effect within four minutes, and had peaked and passed by thirty minutes.
So here's what's going on in your brain on mushrooms.
Psilocybin shuts down activity in the parts of the brain that
-regulate our sense of self
-integrate our sense of awareness with our sense of the present
It also decreases activity in the Default Mode Network
-scientists aren't entirely in agreement about what this part of the brain does
-it's believed to be instrumental in "maintaining a balanced sense of consciousness and ego through self-reflection," says the Discovery.com article
Stronger trips were reported by those for whom these parts of the brain were reduced the most.
More specifics on which parts of the brain eased off:
The Anterior Cingulate Cortex, which plays a role in
-regulating heart rate and blood pressure
-detecting physical pain
**This part of the brain is often found to be overactive in the chronically depressed. Dr. Nutt is looking into using psilocybin in combination with therapy to treat depression.
The Medial Prefrontal Cortex, which plays a role in
-planning complex cognitive behaviour
-moderating social behaviour
-as Wikipedia puts it: "Many authors have indicated an integral link between a person's personality and the functions of the prefrontal cortex."
The Posterior Cingulate Cortex, which
-acts as a "neural substrate for human awareness"
-helps with pain and memory retrieval
-according to wiki: "may also be involved in the capacity to understand what other people believe"
I'm in no way qualified to interpret this data. But it seems like the lessening of these parts of the brain brings about that sense I've experienced on mushrooms of not being a separate entity. Of being taken out of your regular self. Of seeing a bigger picture, and understanding that you're a part of it too. And so is everything, everywhere.
Comedian/philosopher/visionary Bill Hicks said it pretty damn well:
Three weeks ago two of my friends and I went to a ranch in Fredericksburg, Texas, and took what Terence McKenna calls "a heroic dose." Five dried grams. Let me tell you, our third eye was squeegeed quite cleanly. Wow! And I'm glad they're against the law, 'cause you know what happened when I took 'em? I laid in a field of green grass for four hours, going "My God, I love everything." The heavens parted, God looked down and rained gifts of forgiveness onto my being, healing me on every level, psychically, physically, emotionally. And I realized our true nature is spirit, not body, that we are eternal beings, and God's love is unconditional and there's nothing we can ever do to change that. It is only our illusion that we are separate from God, or that we are alone. In fact the reality is we are one with God and He loves us. Now, if that isn't a hazard to this country... Do you see my point? How are we gonna keep building nuclear weapons, you know what I mean? What's gonna happen to the arms industry when we realize we're all one. It's gonna fuck up the economy! The economy that's fake anyway! Which would be a real bummer. You can see why the government's cracking down on idea of feeling unconditional love.
(If you can stand the herky-jerky quality of the video, check out the clip below - it's visual part of the audio used on Hicks' masterpiece comedy album Rant in E Minor)