For the third time, Joe and Rolf talk to Dr. Balazs Szigeti about psychedelics for the treatment of depression. This time, Balazs discusses his recent paper that shows an equivalence between psychedelics and traditional medications in effectiveness for treating depression. This is surprising, given the size of effects that have been demonstrated in some early psychedelic trials, and can be accounted for, in part, by patient expectations.

Williams ZJ, Barnett H, Szigeti B. Psychedelic Therapy vs Antidepressants for the Treatment of Depression Under Equal Unblinding Conditions: A Systematic Review and Meta-Analysis. JAMA Psychiatry. Published online March 18, 2026. doi:10.1001/jamapsychiatry.2025.4809

 Balazs Szigeti: Unblinding Effects in Psychedelic Research

On this episode, Rolf and Joe talk to Dr. Valerie Bonnelle, a cognitive neuroscientist interested in the relation of processes in the body to peak experiences. We discuss her paper showing how heart rate variability and the interplay between the sympathetic and parasympathetic nervous systems closely tracks phenomenological experience during the use of the psychedelic DMT.



Bonnelle, V., Feilding, A., Rosas, F. E., Nutt, D. J., Carhart-Harris, R. L., & Timmermann, C. (2024). Autonomic nervous system activity correlates with peak experiences induced by DMT and predicts increases in well-being. Journal of Psychopharmacology, 38(10), 887-896.

Dr. Valerie Bonnelle: The autonomic nervous system and peak experience

What do the National Institutes of Health (NIH) do, and who works there? Rolf and Joe talk to Dr. Bradley Cooke [https://www.niddk.nih.gov/about-niddk/staff-directory/biography/cooke-brad], who works at the NIH as a Program Director in the Division of Diabetes, Endocrinology, and Metabolic Diseases (located within the National Institute of Diabetes and Digestive and Kidney Diseases). Dr. Cooke talks about the research he conducted when he was in the academic world, including work on the biology of attraction and sex differences in the brain, and then discusses how the NIH monitors and guides the national research agenda, some of the essential and groundbreaking research the NIH has funded, as well as exciting research trends coming our way.

Dr. Bradley Cooke: The National Institutes of Health

Fresh from Psychedelic Science 2025, Dr. Steve Levine, the chief patient officer at Compass Pathways, talks to us about new Phase 3 results for psilocybin in treating depression.

Compass Pathway's Dr. Steve Levine

Joe reports back from the Psychedelic Science conference held recently again in Denver, Colorado. After some discussion about the conference, Joe speaks with Balasz Szigeti (who was on the podcast in 2023) about his recent work on the "Placebo Suppression Effect" in psychedelic research.

Psychedelic Science 2025

Joe and Rolf talk to blind activist and friend of the show Josh Miele.  Josh, a MacArthur Genuis Award winner and prodigious sushi eater, has just come out with a new autobiographical book called "Connecting Dots: A Blind Life".   We talk about his life growing up  in Park Slope, his freewheeling youth, the dog vs. cane debate, and his career as a blind accessibility scientist and inventor.

Joshua Miele: Connecting Dots

Rolf and Joe talk to NYU philosopher Jeff Sebo about his new book "The Moral Circle", which makes the case for expanding our circle of who is deserving of ethical consideration to nonhuman animals, insects, plants, and AI systems.

Expanding our Moral Circle with Philosopher Jeff Sebo

Rolf and Joe wrap up their 3-part series on dreaming with Finnish neuroscientist and philosopher Antti Revonsuo. Dr. Revonsuo is the originator of the Threat Simulation theory of dreams, which suggests that dreams are simulated worlds in which we may practice threatening situations. Topics include the history and methodology in dream research, how our brains create simulated worlds, the particular nature of the simulated dream world, and how this applies to waking consciousness. We base our discussion on three forthcoming papers:

Revonsuo, A. (in press) Toward a Metaphysics of Consciousness: Science and the Fundamental Nature of Subjective Experience. To appear in The Scientific Study of Consciousness: Experimental and Theoretical Approaches. (Springer Nature).

Revonsuo, A. & Tuominen, J. (in press) The Concept of Dreaming as a World. To appear in Threshold Worlds (Oxford University Press).

Revonsuo, A., Valli, K., & Tuominen, J. (in preparation) Evolutionary Simulation Theories of Dreaming.



Dreaming (part 3) with Antti Revonsuo

In their second episode in a series on dreaming, Joe and Rolf are joined by Dr. Pilleriin Sikka, a Stanford neuroscientist who is currently studying the therapeutic value of dreams under anesthesia. 

Hack, L. M., Sikka, P., Zhou, K., Kawai, M., Chow, H. S., & Heifets, B. (2024). Reduction in Trauma-Related Symptoms After Anesthetic-Induced Intra-Operative Dreaming. American Journal of Psychiatry, 181(6), 563-564.

https://psychiatryonline.org/doi/full/10.1176/appi.ajp.20230698

Dreams and Anaesthesia: Guest Pilleriin Sikka

Why do we dream, and what is the meaning of our dreams? Rolf and Joe talk about several ideas about dreaming, including a new theory by David Eagleman called the "defensive activation theory", which proposes that dreams are like a screen saver to keep the visual parts of the brain from being overtaken by other senses.

Eagleman, D. M., & Vaughn, D. A. (2020). The Defensive Activation theory: dreaming as a mechanism to prevent takeover of the visual cortex. bioRxiv, 2020-07.

Why do we dream?

CogNation is a podcast by Rolf Nelson and Joe Hardy, two cognitive psychologists interested in the future of brain science and technology. We explore relevant topics in the areas of cognitive science, technology, AI, and philosophy. Although we dabble with dystopian implications of new technologies (such as the impending robopocalypse), we are led by our curiosity and try to keep it light and fun. https://www.facebook.com/CognationPodcast/ email: cognationpodcast@gmail.com

Joe Hardy

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