Author Michael Pollan and neuroscientist Christof Koch debated consciousness and psychedelics during a public event at UC Berkeley. Moderated by Shayla Love and presented by Cal Performances, the discussion examined how these substances alter human perception and the enduring challenge of objectively measuring subjective experience.
The conversation brought together two distinct perspectives on the mind. Michael Pollan, a Knight Professor of Science and Environmental Journalism emeritus at the Graduate School of Journalism and co-founder of the UC Berkeley Center for the Science of Psychedelics in 2020, discussed his long-standing exploration of psychedelics and perception alongside Christof Koch.
The event was organized by Cal Performances with support from the Steven & Alexandra Cohen Foundation and featured in the Berkeley Talks podcast. Michael Pollan’s book A World Appears builds on the framework established in his earlier work, How to Change Your Mind.
The Challenge of Measuring Subjective Experience
Evaluating consciousness objectively remains a central hurdle in modern neuroscience. Christof Koch explained during the discussion that there is no direct instrument to measure a conscious state. Instead, researchers rely entirely on inference, assuming that a person who shares biological traits, speech patterns, and behaviors possesses a mind similar to their own.
This reality led to a lighthearted moment regarding a long-running scientific wager between the two thinkers. Koch acknowledged on stage that he had lost a bet made twenty-five years earlier to identify precise neural correlates of consciousness within that timeframe. Fulfilling the terms of the wager four years prior in New York, Koch presented Pollan with six bottles of wine before the pair renewed the bet for another quarter-century.
Neocortex Anatomy and Brain Stimulation
Anatomically, the outermost layer of the brain known as the neocortex is essential for conscious experience. However, clinicians and researchers continue to debate which specific regions drive the phenomenon.
Neurosurgeons routinely stimulate the rear portion of the brain to provoke specific conscious events, such as memories, tingling sensations, or pain. Conversely, the frontal region of the brain is often termed non-eloquent by surgeons because direct electrical stimulation there produces no immediate sensory output.
No, I’m conscious. I hear and see.
Dan Dennett, via Berkeley Talks
Even debates among philosophers regarding the nature of perception surfaced during the panel. Koch referenced discussions with the philosopher Dan Dennett, noting that while Dennett viewed consciousness as an illusion, it remains an experience shared by everyone.
Pragmatic Value of Psychedelic Insights
For Pollan, exploring altered states through research and personal writing defamiliarized ordinary consciousness, much like art shifts a viewer’s perspective. Drawing on the philosophical framework of William James regarding mystical experiences, Pollan argued that the validity of an insight can be judged by its practical utility and whether it functions as a workable hypothesis about reality.
So even forgetting about the metaphysics, even accepting, OK, it’s some weird, something your brain does on a psychedelic, if it helps patients … Who cares?
Michael Pollan, via Berkeley Talks
Whether examining deep metaphysics or the immediate biochemical effects of a psychedelic substance, the primary measure of value rests on tangible benefits for patients. That pragmatic baseline allows researchers to study therapeutic outcomes independently of the profound philosophical questions raised by the experience.