Expectation-induced modulation of metastable activity underlies faster coding of sensory stimuli

TL;DR

This paper presents a computational model explaining how expectation speeds up sensory coding by modulating metastable cortical activity, supported by experimental data from the gustatory cortex of rats.

Contribution

It introduces a novel recurrent spiking network model demonstrating how expectation influences intrinsic cortical dynamics to enhance sensory processing.

Findings

Model predictions confirmed by experimental data

Expectation modulates metastable activity to accelerate sensory coding

Provides a biologically plausible mechanism for expectation effects

Abstract

Sensory stimuli can be recognized more rapidly when they are expected. This phenomenon depends on expectation affecting the cortical processing of sensory information. However, virtually nothing is known on the mechanisms responsible for the effects of expectation on sensory networks. Here, we report a novel computational mechanism underlying the expectation-dependent acceleration of coding observed in the gustatory cortex (GC) of alert rats. We use a recurrent spiking network model with a clustered architecture capturing essential features of cortical activity, including the metastable activity observed in GC before and after gustatory stimulation. Relying both on network theory and computer simulations, we propose that expectation exerts its function by modulating the intrinsically generated dynamics preceding taste delivery. Our model, whose predictions are confirmed in the experimental data, demonstrates how the modulation of intrinsic metastable activity can shape sensory coding and mediate cognitive processes such as the expectation of relevant events. Altogether, these results provide a biologically plausible theory of expectation and ascribe a new functional role to intrinsically generated, metastable activity.