RT Journal Article SR Electronic T1 Expectation-induced modulation of metastable activity underlies faster coding of sensory stimuli JF bioRxiv FD Cold Spring Harbor Laboratory SP 199380 DO 10.1101/199380 A1 L. Mazzucato A1 G. La Camera A1 A. Fontanini A1 Fontanini Alfredo A1 La Camera Giancarlo YR 2018 UL http://biorxiv.org/content/early/2018/11/01/199380.abstract AB 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.