Dynamical interactions reconfigure the gradient of cortical timescales

Abstract

Behavioral responses are brain-state dependent and rely on the coordinated activity of brain areas. Their exchange of information within the network can be represented as functional links establishing a spatiotemporal pattern, evolving over time and scales. Network neuroscience offers useful tools that may guide our understanding of these patterns organisation. Here we used source-reconstructed Magnetoencephalography signals from a large healthy cohort, and estimated a link-specific time-scale as the information decay-time. Their distribution allowed the identification of two anatomically distinct and functionally coherent networks. Rapidly-decaying links define a fast-updating networK (FUN), which includes regions typically involved in the processing of external stimuli. Slow-decaying links define a slow-updating network (SUN), which comprises hierarchically higher regions, classically involved in the integration of such stimuli. Finally, we show that only a subset of the brain regions belong to both subnetworks, which we name the multi-storage core (MSC). The MSC is hypothesized to play a role in the communication between the (otherwise) temporally segregated subnetworks.

Neuronal Avalanches in Naturalistic Speech and Music Listening

“…This hierarchical structure is preserved during the course of mammalian evolution, despite the increase of brain volume (62); it is characteristic of individual brains, and alterations in its organization lead to mental and neurological disease (65). However, differently than structural features, brain function is highly dynamic and the topography of timescales can vary over time both in rest (66), and task (67).…”

“…While several measures for the signals timescale have been proposed (64,66), here for illustrative purposes we evaluated the timescales as the area before the first τ minimum; Fig. S4.A, left).…”