A computational architecture incorporating shallow brain networks: integrating parallel cortical and subcortical processing

TL;DR

This paper introduces a brain-inspired computational model that combines cortical and subcortical processing to replicate decision-making behavior in primates.

Contribution

The novel contribution is a biologically plausible model integrating parallel cortical and subcortical pathways based on neuroanatomical evidence.

Findings

The model replicates human and monkey behavior in perceptual decision-making tasks.

Subcortical structures handle easy decisions while cortical hierarchy handles complex ones.

The model works with both convolutional and predictive coding network implementations.

Abstract

Artificial neural networks commonly have deep hierarchical structures that were originally inspired by the neuroanatomical evidence of cortico-cortical connectivity pattern found in the mammalian brain. Largely under-represented in those models are non-hierarchical aspects of brain architecture, namely the subcortical pathways and the interactions between cortical and subcortical areas regardless of their hierarchical locations. Inspired by this principle, we present a computational model combining cortical hierarchical processing with subcortical pathways based on neuroanatomical evidence. We show the versatility of our model by implementing the cortical hierarchy in two alternative ways—a convolutional feedforward network and a predictive coding network. Both model variants can replicate behavioral observations in humans and monkeys on a perceptual context-dependent decision-making task. The model also reveals that subcortical structures lead decisions for easy trials while the more complex hierarchical network is necessary for the harder trials. Our results suggest that the parallel cortico-subcortical processing explored in the model represents a fundamental property that cannot be neglected in understanding the computational principles used by the brain.

Image 1

•Biologically-plausible computational model combining cortical and subcortical pathways.•Compatible with both convolutional and predictive coding networks.•Model replicates primate behavior in go/no-go tasks.•Subcortex drives easy decisions; cortical hierarchy drives difficult ones.

Biologically-plausible computational model combining cortical and subcortical pathways.

Compatible with both convolutional and predictive coding networks.

Model replicates primate behavior in go/no-go tasks.

Subcortex drives easy decisions; cortical hierarchy drives difficult ones.

Figures