Predictive Coding with Bayesian Priors via Proximal Gradients

· Source: Machine Learning · Field: Technology & Digital — Artificial Intelligence & Machine Learning · Depth: Expert, quick

Summary

A new theoretical framework recasts predictive coding as continuous-time proximal gradient descent applied to a regularized maximum-a-posteriori (MAP) objective. For single-level problems, this approach demonstrates that proximal gradient descent precisely describes a leaky firing-rate network, where elements like membrane leak, recurrent matrix, and synaptic drive derive from a single optimization principle, aligning with Rao and Ballard's circuit. The prior determines the network's nonlinearity via its proximal operator, while likelihood precision sets observation gain. For multi-level hierarchies, a classical variable-splitting relaxation of the deep MAP problem yields hierarchical predictive coding, connecting local and distributed solvers by transforming the directed generative chain into an undirected Markov random field.

Key takeaway

For AI scientists researching biologically plausible learning or neural network dynamics, this framework offers a unified optimization perspective on predictive coding. You should consider how this reinterpretation, linking network components to a MAP objective via proximal gradients, could inform the design or analysis of hierarchical generative models, potentially simplifying their theoretical underpinnings and implementation.

Key insights

Predictive coding is reinterpreted as continuous-time proximal gradient descent on a regularized maximum-a-posteriori objective.

Principles

Method

Recasts predictive coding as continuous-time proximal gradient descent on a regularized MAP objective, employing variable-splitting relaxation for hierarchical structures.

Topics

Best for: Research Scientist, AI Scientist

Related on AIssential

Open in AIssential →

Editorial summary, takeaway, and curation by AIssential. Original article published by Machine Learning.