
The Power of a Single Neuron, How Brains Learn, and Simulating the Brain | Dr. Konrad Kording
Juan Benet PodcastShow Notes
New episode with Dr. Konrad Kording, professor of bioengineering and neuroscience at the University of Pennsylvania and co-director of CIFAR's Learning in Machines & Brains program. Konrad works at the intersection of causality, machine learning, and neuroscience, building rigorous methods for causal reasoning when experiments aren't possible — and challenging how researchers interpret neural data and build AI.
Konrad argues the most promising path to understanding how the brain works is to read the brain’s wiring directly, down to the molecular detail of each connection, and to build compilers and simulations to understand the brain’s computation directly.
In this episode we go deep into how neurons work, how neurons wire together, and how organic and artificial neural networks differ. We discuss why organic neurons are doing much more; how a model of a single organic neuron can solve MNIST — computing more like a 3-layer artificial neural network; how the brain might learn by solving credit assignment with only local signals; how to approximate backprop without a global algorithm; why AI and humans are intelligent along different dimensions; why Konrad isn’t very worried about AI replacing us; economic models of intelligence and physical work; and much more.
Konrad is a brilliant, contrarian thinker who explains complex concepts very intuitively. It is a solid computational neuroscience primer. I hope you enjoy this conversation as much as I did! Other links to this episode and references below.
Topics covered:
00:00:00 Introduction 00:01:01 How organic neurons work 00:24:13 How the brain learns: circuits and credit assignment 00:45:29 Recording the brain 00:52:47 Why simulating brains is hard 01:05:00 A new approach: connectomes and compilers 01:21:00 Why simulate brains? 01:29:50 How AI and human intelligence differ 01:41:04 Evolution, intelligence and AI risk 01:52:42 Robotics, causality, and the roots of intelligence 02:05:53 AI for science and scientific rigor 02:13:05 The economics of intelligence 02:27:50 A hopeful future
Links From the Podcast Episode
Guest + Organizations KordingLab: kordinglab.com KordingLab on GitHub: https://github.com/KordingLab KordingLab on X: https://x.com/kordinglab Papers directly from Konrad Kording's lab: Can Single Neurons Solve MNIST? The Computational Power of Biological Dendritic Trees (2020) Comparing Dendritic Trees with Actual Trees (2023) (Artificial) Intelligence Saturation and the Future of Work (2025) Compiling Molecular Ultrastructure into Neural Dynamics (2026) Referenced external papers: Millisecond-timescale, genetically targeted optical control of neural activity (2005) Dopamine Reward Prediction Error Coding — Wolfram Schultz (2016) Single Cortical Neurons as Deep Artificial Neural Networks — Beniaguev, Idan Segev & London (2021) Neural Signal Propagation Atlas of C. elegans — Randi, Sharma, Dvali & Leifer (Andrew Leifer's lab) (2023) Books & Media: Causal Learning: Psychology, Philosophy, and Computation — Alison Gopnik & Laura Schulz Juan & Protocol Labs Juan Benet on X Protocol Labs PL Neuro Disclaimer
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