Huberman Lab

Your Brain's Logic & Function | Dr. David Berson

In this episode, my guest is Dr. David Berson, Professor and Chairman of Neuroscience at Brown University. Dr. Berson discovered the neurons in your eye that set your biological rhythms for sleep, wakefulness, mood and appetite. He is also a world-renowned teacher of basic and advanced neuroscience, having taught thousands of university lectures on this topic. Many of his students have become world-leading neuroscientists and teachers themselves. Here Dr. Berson takes us on a structured journey into and around the nervous system, explaining how we perceive the world and our internal landscape, how we balance, see and remember, how we learn and perform reflexive and deliberate actions, how we visualize and imagine in our mind and how the various circuits of the brain coordinate all these incredible feats. We discuss practical and real-life examples of neural circuit function across the lifespan. Dr. Berson gives us a masterclass in the nervous system—one that, in just under two hours, will teach you an entire course's worth about the brain and how yours works. For an up-to-date list of our current sponsors, please visit our website: https://www.hubermanlab.com/sponsors. Previous sponsors mentioned in this podcast episode may no longer be affiliated with us. Social: Instagram - https://www.instagram.com/hubermanlab Twitter - https://twitter.com/hubermanlab Facebook - https://www.facebook.com/hubermanlab Website - https://hubermanlab.com Newsletter - https://hubermanlab.com/neural-network Links: InsideTracker Interview - https://blog.insidetracker.com/longevity-by-design-andrew-huberman Dr. Berson's Webpage - https://vivo.brown.edu/display/dberson Eyewire - (Contribute to Neuroscience Research from Home/Computer - https://eyewire.org/explore Best Neuroscience Textbook (NOTE this is a TEXTBOOK) - https://amzn.to/3lZWrL4 Book - We Know It When We See It by Richard Masland - https://amzn.to/31S60Vp Timestamps: 00:00:00 Dr. David Berson 00:02:55 Sponsors: Athletic Greens, InsideTracker, Magic Spoon 00:08:02 How We See 00:10:02 Color Vision 00:13:47 “Strange” Vision 00:16:56 How You Orient In Time 00:25:45 Body Rhythms, Pineal function, Light & Melatonin, Blueblockers 00:34:45 Spending Times Outdoors Improves Eyesight 00:36:20 Sensation, Mood, & Self-Image 00:41:03 Sense of Balance 00:50:43 Why Pigeons Bob Their Heads, Motion Sickness 01:00:03 Popping Ears 01:02:35 Midbrain & Blindsight 01:10:44 Why Tilted Motion Feels Good 01:13:24 Reflexes vs. Deliberate Actions 01:16:35 Basal Ganglia & the “2 Marshmallow Test” 01:24:40 Suppressing Reflexes: Cortex 01:33:33 Neuroplasticity 01:36:27 What is a Connectome? 01:45:20 How to Learn (More About the Brain) 01:49:04 Book Suggestion, my Berson Appreciation 01:50:20 Zero-Cost ways to Support the HLP, Guest Suggestions, Sponsors, Patreon, Thorne Please note that The Huberman Lab Podcast is distinct from Dr. Huberman's teaching and research roles at Stanford University School of Medicine. The information provided in this show is not medical advice, nor should it be taken or applied as a replacement for medical advice. The Huberman Lab Podcast, its employees, guests and affiliates assume no liability for the application of the information discussed.

AHAndrew HubermanhostDBDr. David Bersonguest

Dec 13, 2021·1h 52m·Watch on YouTube ↗

📖 CHAPTERS

1. 1
   0:00 – 7:00

   Intro, Guest Background, and Episode Overview

   Andrew Huberman introduces the podcast, his guest Dr. David Berson, and Berson’s key discoveries about light-sensitive retinal cells that set circadian rhythms. He frames Berson as a long-time mentor and explains that the episode will walk from the periphery of the nervous system into deeper structures to build a logical picture of how the brain works.

2. 2
   7:00 – 21:00

   Sponsors and Lifestyle Context (Athletic Greens, InsideTracker, Magic Spoon)

   Huberman reads sponsor ads and briefly explains his own daily routines around nutrition, fasting, and low-carb daytime eating to support alertness and sleep. These segments contextualize health and lifestyle factors that relate indirectly to the neuroscience themes of the episode.

3. 3
   21:00 – 35:00

   How Vision Works: Photons, Photoreceptors, and Color

   Berson explains how light is both wave and particle, how photoreceptors convert photons into neural signals, and how different cone types underlie color vision. The conversation touches on electromagnetic spectrum, subjective color experience, and differences between human and animal color perception.

4. 4
   35:00 – 45:00

   Melanopsin Cells: ‘Fly Eye’ in the Human Retina and Non-Image-Forming Vision

   The discussion shifts to melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs), which act as internal light meters. Berson explains that these cells are photoreceptors in the ganglion cell layer that use an invertebrate-like signaling cascade and primarily encode brightness for non-conscious functions.

5. 5
   45:00 – 56:00

   Circadian Clocks, SCN, and Light’s Grip on Your Physiology

   Berson describes the suprachiasmatic nucleus (SCN) as the master circadian pacemaker coordinating millions of cellular clocks, and explains how retinal input synchronizes this system. They explore blind individuals’ circadian drift, jet lag, and how the SCN influences hormones and autonomic state via the hypothalamus.

6. 6
   56:00 – 1:10:00

   Melatonin, Light at Night, and Misconceptions About ‘Blue Light’ Only

   The conversation narrows to how the SCN controls melatonin release from the pineal gland via sympathetic pathways, and why light at night powerfully suppresses melatonin. They clarify that while blue light is most effective per photon, very bright light of any color can strongly suppress melatonin, challenging simplistic ‘blue light only’ narratives.

7. 7
   1:10:00 – 1:22:00

   Brightness Pathways to Mood and Higher Cognition: Thalamus and Frontal Cortex

   Berson describes a lesser-known retinal pathway that travels through a non-classical thalamic nucleus to frontal cortical areas involved in planning and self-image. Work from Samer Hattar’s lab suggests that mistimed activation of this pathway can induce depression-like behaviors in animals, and blocking it can prevent light-induced depression.

8. 8
   1:22:00 – 1:35:00

   Vestibular System, Visual-Vestibular Integration, and Motion Sickness

   The conversation moves to the vestibular system in the inner ear, how it senses head movement through fluid-filled semicircular canals, and how its signals are compared to vision. They explain image stabilization reflexes, why pigeons bob their heads, and how mismatches between vestibular and visual cues generate motion sickness.

9. 9
   1:35:00 – 1:46:30

   Cerebellum: Error Correction and Motor Learning for Vision and Movement

   Berson characterizes the cerebellum as an ‘air traffic control’ system that takes in wide-ranging sensory and motor information to coordinate behavior. He highlights the flocculus, which integrates vestibular and visual inputs for gaze stabilization, and notes the cerebellum’s key role in fine-tuning movement and learning new motor skills.

10. 10
    1:46:30 – 1:50:00

    Ear Pressure, Planes, and Simple Physiology of the Eustachian Tube

    They briefly detour into why ears ‘pop’ during altitude changes and how plugging the nose and blowing or sucking equalizes middle-ear pressure. Berson explains that the key is opening the Eustachian tube so that pressure can equilibrate across the eardrum.

11. 11
    1:50:00 – 2:02:00

    Midbrain, Superior Colliculus, and Multisensory Reflex Behavior

    The discussion returns to the midbrain, especially the superior colliculus (optic tectum), as a key hub for integrating visual, auditory, and other sensory cues to drive rapid orienting and defensive responses. Berson draws examples from non-mammalian vertebrates and rattlesnakes, highlighting that many critical visual functions never reach conscious awareness.

12. 12
    2:02:00 – 2:07:00

    Why Moving Through Space Can Feel Good

    Huberman raises the question of why tilting and moving through space (e.g., skating, surfing, roller coasters) often feels pleasurable. Berson doesn’t offer a definitive mechanistic answer but speculates about reward from agency, mastery, and coordinated movement, acknowledging dopamine’s widespread modulatory role.

13. 13
    2:07:00 – 2:21:00

    Basal Ganglia, Cortex, and Go/No-Go Control of Behavior

    They discuss basal ganglia as deep forebrain structures intertwined with cortex that help implement decisions to act or to withhold action. Through examples like the marshmallow test and resisting phone checking, they illustrate how these circuits mediate motivation, self-control, and the ability to override reflexive behavior.

14. 14
    2:21:00 – 2:34:00

    Cortex, Visual Maps, and Extreme Plasticity (Braille and Blindness)

    The focus returns to cortex, especially visual cortex, with its multiple topographic maps and specialized areas. Berson emphasizes that while neurons can be highly specialized, cortical tissue is also remarkably plastic and can be repurposed, illustrated by the case of an early-blind woman whose visual cortex had become essential for braille reading.

15. 15
    2:34:00 – 2:46:00

    Connectomics: Mapping the Brain’s Wiring in Full Detail

    Berson introduces connectomics as the exhaustive mapping of synaptic connections using serial electron microscopy. He explains how these wiring diagrams complement physiological studies by revealing unexpected cell types and synapses, driving new hypotheses about circuit function.

16. 16
    2:46:00

    Participating in Neuroscience and How to Learn More

    The episode closes with advice on how non-specialists can learn about and even contribute to neuroscience, including through citizen-science projects like EyeWire and accessible books. Huberman and Berson emphasize the richness of modern neuroscience and encourage following curiosity into specific subfields.