Your brain is not listening to this. It already guessed what you were going to hear — before you heard it — and it's just checking whether it was right.

That's predictive coding theory. And in Episode 1 of The Latent State, we dig into the paper that tried to catch this process in action — in real primate brains, in real time, with 128 electrodes screwed directly into a monkey's skull. Because science.

The paper is Chao et al. (2018) from Neuron — one of the most mechanistically detailed studies of hierarchical predictive coding ever published. We cover the neural architecture, the gamma and alpha/beta frequency dissociation, the data-driven decomposition method, and — because this is The Latent State — exactly where the evidence is strong, where it's overstated, and where two monkeys are just two monkeys.

Welcome to the show.

Paper: Chao et al. (2018). Large-Scale Cortical Networks for Hierarchical Prediction and Prediction Error in the Primate Brain. Neuron, 100, 1252–1266.

Key concepts covered: Predictive coding, local-global paradigm, ECoG, PARAFAC tensor decomposition, gamma and alpha/beta oscillations, Granger causality, prediction error hierarchies, free energy principle

Further reading:

• ​Rao & Ballard (1999), Nature Neuroscience — the computational foundation
• ​Clark (2013), Behavioral and Brain Sciences — the broadest theoretical synthesis
• ​Friston (2010), Nature Reviews Neuroscience — the free energy formulation
• ​Bekinschtein et al. (2009), PNAS — the original local-global paradigm