Psychedelics: The scientific renaissance of mind-altering drugs | Sam Harris, Michael Pollan & more

Psychedelics: The scientific renaissance of mind-altering drugs
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Having been repressed in the 1960s for their ties to the counterculture, psychedelics are currently experiencing a scientific resurgence. In this video, Michael Pollan, Sam Harris, Jason Silva and Ben Goertzel discuss the history of psychedelics like LSD and psilocybin, acknowledge key figures including Timothy Leary and Albert Hoffman, share what the experience of therapeutic tripping can entail, and explain why these substances are important to the future of mental health.

There is a stigma surrounding psychedelic drugs that some scientists and researchers argue is undeserved. Several experiments over the past decades have shown that, when used correctly, drugs like psilocybin and LSD can have positive effects on the lives of those take them. How they work is not completely understood, but the empirical evidence shows promise in the fields of curbing depression, anxiety, obsession, and even addiction to other substances.

“There’s a tremendous amount of insight that can be plumbed using these various substances. There’s also a lot of risks there, as with most valuable things,” says artificial intelligence researcher Ben Goertzel. He and others believe that by making psychedelics illegal, modern governments are getting in the way of meaningful research and the development of “cultural institutions to guide people in really productive use of these substances.”

Read Michael Pollen’s book “How to Change Your Mind: What the New Science of Psychedelics Teaches Us About Consciousness, Dying, Addiction, Depression, and Transcendence” at

MICHAEL POLLAN: How do these psychedelics work? Well, the honest answer is we don’t entirely know, but we know a few things. One is they fit a certain receptor site: the serotonin 5-HT2A receptor. And they look a lot like serotonin if you look at the molecular models of them and, in fact, LSD fits that receptor site even better than serotonin does and it stays there longer. And that’s why the LSD trip can last 12 hours. What happens after that we don’t really know. It’s an agonist to that receptor. So it increases its activity. And this, you know the neuroscientists say lead to a cascade of effects which is shorthand for don’t really know what happens next. But one thing we do know, or we think we know, is that it appears that one particular brain network is deactivated or quieted. And that is the default mode network. This was discovered not very long ago by a researcher in England named Robin Carhart-Harris who was dosing people with psilocybin and LSD and then sliding them into an MRI machine, to take an FMRI a functional magnetic resonance image. The expectation I think was that people would see an excitation of many different networks in the brain. You know, that’s what the kind of mental fireworks sort of foretold, but he was very surprised to discover that one particular network was down-regulated and that was this default mode network.

So what is that? Well, it’s a tightly linked set of structures connecting the prefrontal cortex to the posterior cingulate cortex, to the deeper older centers of emotion and memory. It appears to be involved in things like self-reflection, theory of mind, the ability to impute mental states to others, mental time travel, the ability to project forward in time and back, which is central to creating an identity, right? You don’t have an identity without a memory and the so-called autobiographical memory, the function by which we construct the story of who we are by taking the things that happened to us and folding them into that narrative. And that appears to take place in the posterior cingulate cortex. So, you know, to the extent the ego can be said to have a location in the brain it appears to be this, the default mode network. It’s active when you’re doing nothing. When your mind is wandering. It can be very self-critical, it’s where self-talk takes place. And that goes quiet. And when that goes quiet, the brain is sort of as one of the neuroscientists put it, let off the leash, because those ego functions, that self idea is a regulator of all mental activity and kind of, you know, the brain is a hierarchical system and the default mode network appears to be at the top. It’s kind of the orchestra conductor or corporate executive. And you take that out of the picture, and suddenly you have this uprising from other parts of the brain and you have networks that don’t ordinarily communicate with one another suddenly striking up…

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