Understanding Your Brain's Logic & Function | Dr. David Berson
Join Dr. David Berson, a noted neuroscience professor at Brown University, as he delves into the brain's workings. He explains the fascinating way our eyes perceive light and the intricate mechanisms behind color vision. Discover how specialized cells regulate our biological rhythms and the connection between vision and balance. With engaging examples, he illustrates how our nervous system coordinates movement, perception, and decision-making, offering insights into both the science of seeing and the reality of sensory processing.
Top snips
How we see color
9:18 – 11:52
Light is electromagnetic energy — we decode wavelength with three cone types in the retina.
- Each cone has a different pigment tuned to specific wavelengths.
- The brain compares these signals to create color (reds, greens, blues).
Is your “red” the same as mine? Biology is similar, but subjectivity remains.
It's a deep philosophical question.
— David Berson
A hidden light sensor: ipRGCs & melanopsin
16:32 – 22:32
There are retinal ganglion cells that are intrinsically photosensitive (melanopsin) — they sense overall brightness, not image detail.
They use a primitive cascade more like insect eyes, and they inform your brain about time of day and ambient light.
It's the difference between knowing what the objects are on the table and knowing whether it's bright enough to be daylight right now.
— David Berson
Light → melatonin → mood & timing
30:26 – 32:35
Light through ipRGCs reaches the SCN (master clock) and via autonomic pathways controls the pineal gland → melatonin.
Practical rules:
- Bright light (especially daylight) during day → alertness & mood.
- Bright light at night → suppresses melatonin (any wavelength if intense).
Get morning sun; avoid bright night light.
Balance, motion sickness & the cerebellum
40:26 – 58:30
The inner ear's vestibular organs sense head rotation (3 axes) and feed reflexes that stabilize gaze.
Conflict between vision and vestibular signals (e.g., reading in a moving car) causes nausea.
The cerebellum acts as an error-corrector and integrates visual + vestibular inputs to refine movement and reduce sickness over time.
Basal ganglia: Go / No‑Go control
1:16:21 – 1:23:12
Basal ganglia work with cortex to implement decisions — execute actions or suppress them (the marshmallow test in neural form).
- Cortex plans and contextualizes.
- Basal ganglia help carry out or withhold actions.
These circuits are plastic: with practice you strengthen restraint or initiation.
Connectomes & brain plasticity
1:35:44 – 1:41:18
Connectomics maps every synapse in a tissue block using serial EM — a wiring diagram of actual circuits.
Why it matters: anatomy reveals hidden cell types and connections, driving testable hypotheses.
Example: visual cortex repurposes for Braille in early blind people — dramatic cortical plasticity.
Science + maps → new discoveries.