Link: https://youtu.be/CV6u2OPN59Q

Duration: 110 min

Transcript: Download plain text

Short Summary

A long-form interview with David Nichols, a retired Purdue medicinal chemistry professor who spent 38 years studying psychedelics and co-founded the Heffter Research Institute, alongside Brian Roth, a serotonin receptor expert who invented DREADDs. The conversation covers psychedelic history, receptor pharmacology, the search for non-hallucinogenic 5HT2A therapeutics, and culminates in a discussion of chemogenetics, mind-machine interfaces, and AI-driven neuroscience. The episode weaves drug-development pragmatism with speculative claims about near-term radical capabilities in brain circuit control.

Key Quotes

1. "So with my technology, I can create the zombie apocalypse. I can eliminate the desire for sleep. I can make you voraciously aggressive. I can increase your appetite for brains. And I can turn off the circuits that are responsible for the sensation of pain. Basically, whatever you can imagine, we can do. We can turn that on and off with a pill. And it's already being used in China in clinical trials. Of course, the Chinese are beating us at everything literally." (00:00:00)
2. "The MDMA for the first PTSD trials, 1.4 kg, 99.97% pure, sold to Rick Doblin for only $4,000." (00:01:00)
3. "If you have a problem in science, it's because you lack imagination. Basically, I tell people, dream bigger. Yeah. Literally anything almost anything you can imagine in my area of science we we can do basically. Okay. I I don't have any doubt." (00:02:52)
4. "Nixon's drug war was a terrible tragedy and nobody really realized it. There was no so there was no funding for research in this field. I was lucky. I had a grant from NAIDA for most of my time at Purdue, but uh no one else was working in the field. And NIDA was only interested in find out why people use them." (00:35:25)
5. "But if we had a medication that worked 50% as well as psilocyum that was safe and effective, I would take that as a win." (01:26:25)

Detailed Summary

Episode Summary: Psychedelic Science, Serotonin Pharmacology, and the Radical Future of Brain Circuit Control

Interviewee Backgrounds

This long-form interview centers on David Nichols and Brian Roth, two foundational figures in serotonin and psychedelic pharmacology, with a second Brian (Caltech-trained) joining later to discuss chemogenetics and the speculative future of brain circuit control.

• David Nichols was a distinguished professor at Purdue University for 38 years in medicinal chemistry and pharmacology, continuously funded by NIMH to study dopamine agonists, psychedelics, and MDMA. He published close to 400 papers and book chapters and founded the Heffter Research Institute in 1993.
• Brian Roth entered the serotonin receptor field in 1983 during a postdoc with Erminio Costa at the NIH, invented DREADDs (now used in 1,000+ labs), discovered the receptor Salvia hijacks (2017), and produced the first atomic-resolution image of LSD bound in a human serotonin receptor.
• Roth has run America's drug screening program for 25 years and holds a $26.9 million DARPA grant for non-hallucinogenic psychedelics.
• A second Brian (Caltech-trained) appears later claiming to have invented chemogenetics and is described by the host of the Giant Shoulders podcast as "super smart."

Heffter Research Institute and Early Funding

The Heffter Research Institute emerged because no institutional funder would touch clinical psychedelic studies, yet it ultimately bankrolled the trials that brought psychedelics back into mainstream medicine.

• Heffter was founded in 1993 because no one was funding clinical psychedelic studies, and has since raised about $10 million, supporting over 156 studies including the Johns Hopkins and NYU cancer trials (2011, 2016) that brought psychedelics back into mainstream medicine.
• Bob Wallace, an early Microsoft founder, donated roughly $100,000/year for several years to support psychedelic research awards.
• "Psychedelic" was a forbidden term in grant applications, akin to "DEI" today; Nichols insisted on the term over "psychotomimetic" or "hallucinogen."
• Nichols wrote a 2004 review on hallucinogens plus a later, widely cited review specifically using the term "psychedelics."

Synthesis Contributions

Nichols quietly supplied kilogram-scale GMP-grade material that undergirded several landmark psychedelic trials, using procedures largely inherited from Sasha Shulgin.

• Nichols synthesized 1.4 kg of 99.97% pure MDMA for Rick Doblin's MAPS phase 1/2 studies at a cost of $4,000 (vendors quoted $100,000+); at phase 3, GMP MDMA cost ~$500,000.
• The procedure came from Sasha Shulgin (aluminum reduction with methylamine hydrochloride and aluminum foil); after two vacuum distillations FDA tests showed no residual aluminum.
• Nichols also made DMT for Rick Strassman (basis of "DMT: The Spirit Molecule") and psilocybin for Johns Hopkins, where 20 grams supported Roland Griffiths' 2016 study of dying patients in existential distress.
• An earlier 2006 Hopkins study found normal individuals rated the psilocybin experience among the five most spiritually significant events of their lives.

Serotonin Receptor Pharmacology

Roth's lab has produced the most detailed receptor-level mapping of psychedelics, in part because the drugs' polypharmacology is now understood to be the rule rather than the exception.

• Roth's early work showed SSRIs do not downregulate 5HT2A, but LSD and the atypical antipsychotic clozapine do; clozapine also blocks LSD's effects in humans.
• Richard Glennon provided the first strong pharmacologic data linking psychedelic effects to 5HT2A binding; Herb Meltzer implicated 5HT2A blockade as a treatment for schizophrenia.
• Roth's recent master analysis covered 318 receptors and 41 psychedelics, motivated by polypharmacology.
• Speculation that 5-MeO-DMT's uniqueness stems from 5HT1A activity was not supported; DMT's putative sigma-receptor selectivity was called "complete nonsense."
• A new database of psychedelics plus non-psychedelic analogs is being used by pharmaceutical companies for drug discovery, with the paper expected to receive 100+ citations.
• Other receptor targets highlighted include 5HT1E, 5HT5A, 5HT6, 5HT7, and orphan receptors (≥50% of GPCRs in the human genome are orphans).
• 5HT2C has 24 protein variants with little known about expression and may attenuate psychedelic effects.

Mechanism of Action Debate

Nichols and Roth disagree on whether psychedelics' mechanism is fundamentally understood, with the disagreement hinging on how to interpret partial agonism at 5HT2A.

• Dave argued the mechanism is unknown; Nichols countered that non-psychedelic serotonergic drugs (bromo-LSD, lisuride) fail to activate the human 5-HT2A receptor in brain slice assays because most assays contain too much receptor reserve.
• Nichols proposed the mechanism is Gq signaling magnitude at 5-HT2A.
• Roth drew an analogy to Arvid Carlsson's dopamine partial-agonist work (leading to aripiprazole), suggesting a similar partial-agonist strategy at 5-HT2A might hit a therapeutic threshold without inducing psychedelic effects.
• John McCorry co-published a paper arguing a specific Gq-activation threshold is needed for psychedelic action; Roth told reviewers to emphasize the threshold concept.

Non-Psychedelic 5HT2A Agonists and the DARPA Grant

DARPA's $26.9 million bet on non-hallucinogenic 5HT2A agonists reflects an enormous unmet need in depression, though early clinical results have been mixed.

• DARPA approached Roth after he floated the idea in a talk, resulting in the $26.9M grant. Motivation: ~1 billion of ~4 billion people will experience depression; a drug working 50% as well as psilocybin or helping 20% of depressed patients would be a "win."
• Roth is a psychiatrist by training who used to see 20+ patients/day, calling it "an unending stream of human suffering."
• Delix Pharmaceuticals (US) is furthest along, but its results were described as "not so encouraging."
• Shang Wang's IHC compounds are reportedly in Phase 2 in China, though Nichols questioned whether they are merely weak partial agonists (functioning as antagonists); 5HT2A antagonists already have known antidepressant activity.
• 2A Biosciences (Dave's company) is developing a 5HT2A agonist for neurotrophic keratitis (diabetic retinal cell loss) at 0.00003% topical concentration — too low to be psychedelic even if it were.
• The DEA classifies compounds as "psychedelic" at Phase 1 based on human reports; the mouse head-twitch assay has no known false negatives.
• Phase 3 trials for these compounds will cost at least $150 million.

Clinical Observations and Drug Approval Outlook

Clinical anecdotes and the regulatory landscape suggest psychedelic therapy is approaching a tipping point, though the first approvals may not be the drugs most people expect.

• Dave described a terminal cancer patient estranged from his brother for 10 years who called him under the influence of a psychedelic to reconcile.
• A man in his late 20s with alcohol use disorder quit drinking after MDMA-assisted therapy at NYU.
• Potential therapeutic applications include existential distress at end of life, substance addiction, OCD, and eating disorders.
• Oregon now offers legal psychedelic therapy for existential crises — described as a surprising acceleration.
• Nichols predicted methylone and psilocybin would be the first psychedelics approved (late that year or next). Methylone is more dopaminergic and lacks 5-HT2B binding, avoiding the valvular heart disease risk of chronic 5-HT2B agonism.
• Rick Doblin was met by Nichols at Esalen while Doblin was a student at New College, where he created his own degree in psychedelic studies; Nichols encouraged him to pursue a PhD or MD.

Safety, History, and Political Context

The drug-development conversation is haunted by decades of federal suppression, and lingering safety questions about psychedelics are still incompletely answered.

• Hallucinogen Persisting Perceptual Disorder (HPPD) can occur even after a single LSD use, though incidence is rare.
• Co-administration of psychedelics with SSRIs is likely safe but unstudied.
• The federal government — specifically Nixon's drug war — is blamed for decades of missing psychedelic research.
• A Nixon administrative assistant reportedly said the administration arrested hippies to strip them of voting rights because they protested Vietnam.
• Nichols had a heart attack in 2019 and retired from Purdue in 2012, then took a sabbatical in Brian Roth's lab at Chapel Hill.
• Dave notes that cryo-electron microscopy has replaced X-ray crystallography for receptor structure work and is improving daily in speed and resolution.

Chemogenetics and the Caltech Brian's Claims

The second half of the episode pivots to a Caltech-trained Brian who claims to have invented chemogenetics and asserts radically expansive capabilities for circuit-level brain control.

• Brian claims his chemogenetics technology can turn specific neural circuits on or off with a pill and is already in clinical trials in China.
• He argues that with sufficient resources, nearly anything in his area of science is achievable within 30 years — except things violating basic physics such as wormhole travel.
• Brian makes striking claims about the technology's capabilities, including eliminating the desire for sleep, inducing voracious aggression, turning off pain circuits, inducing false memories, and creating or suppressing sensations at will.
• Brian joked these capabilities could "literally enable a zombie apocalypse," which the host connects to the Korean horror film Colony, where a biotech leader's virus gives zombies collective electrochemical intelligence.

Mind-Machine Interfaces and AI-Driven Neuroscience

The episode's most speculative territory concerns imminent mind-machine interfaces and AI-driven drug discovery, with predictably conflicting cost assessments.

• Sam Altman has reportedly been given an "unlimited budget" to develop a mind-machine interface; Brian predicts it could arrive within 5 years if civilization continues.
• Brian predicts that in 30 years pills may no longer exist, with AI instead adjusting neural firing to prevent or treat conditions.
• Isomorphic Labs is highlighted as a $2 billion spin-out from DeepMind; a guest pushes back that $2 billion is not a lot of money in drug discovery and predicts Isomorphic Labs will discover this shortcoming soon.

Existential Risks and Civilizational Worry

Brian's technological optimism is paradoxically paired with deep pessimism about whether Western civilization will survive long enough to benefit from these advances.

• Brian says he is "very worried about the future of Western civilization surviving the next 30 years," a concern the host flags as inconsistent with his optimistic technological predictions.
• The host highlights this tension between radical capability and civilizational fragility as a central tension of the discussion.

Podcast Context and Resources

The episode is hosted on the Giant Shoulders podcast, which frames itself as a venue for radical ideas in neuroscience while promoting supplementary resources.

• The Giant Shoulders podcast states its mission to explore radical ideas in biology, neuroscience, and consciousness and make them accessible.
• The show promotes a clips channel plus a free downloadable neuroscience book (referenced 26 times in the episode context).