Metastable States of Multiscale Brain Networks Are Keys to Crack the Timing Problem

Abstract

The dynamics of the environment where we live in and the interaction with it, predicting events, provided strong evolutionary pressures for the brain functioning to process temporal information and generate timed responses. As a result, the human brain is able to process temporal information and generate temporal patterns. Despite the clear importance of temporal processing to cognition, learning, communication and sensory, motor and emotional processing, the basal mechanisms of how animals differentiate simple intervals or provide timed responses are still under debate. The lesson we learned from the last decade of research in neuroscience is that functional and structural brain connectivity matter. Specifically, it has been accepted that the organization of the brain in interacting segregated networks enables its function. In this paper we delineate the route to a promising approach for investigating timing mechanisms. We illustrate how novel insight into timing mechanisms can come by investigating brain functioning as a multi-layer dynamical network whose clustered dynamics is bound to report the presence of metastable states. We anticipate that metastable dynamics underlie the real-time coordination necessary for the brain's dynamic functioning associated to time perception. This new point of view will help further clarifying mechanisms of neuropsychiatric disorders.

Temporal Processing: Neural Correlates and Clinical Relevance

“…As discussed by the authors, these results support the hypothesis that different subcortical networks are preferentially recruited when external cuing of movement induces sensorimotor entrainment compared to when movements are internally initiated (15). T he ability to track time over a wide range of durations (i.e., milliseconds, seconds, minutes, hours, days, months, years) is essential for optimizing interactions with a constantly changing complex world (9,10,(16)(17)(18)(19). Timing is a crucial factor in the sensorymotor processing that generates the intricate, precisely controlled movements required to play a musical instrument, catch a ball, or dance.…”

“…Reviews and meta-analyses of functional imaging (fMRI, positron emission tomography [PET]) studies have probed the neural correlates of many aspects of temporal processing in healthy individuals (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(13)(14)(15). Overall, these studies support the presence of a widespread network of cortical (supplementary motor area, premotor cortex, inferior frontal gyrus, anterior insula, inferior parietal cortex, posterior superior temporal gyrus/sulcus) and subcortical (basal ganglia, thalamus, cerebellum) areas that are variably recruited based on specific task parameters and demands (Figure 1).…”

Brain Networks Underlying Eye’s Pupil Dynamics

“…Pupil size has also been linked to the subjective passage of time (Suzuki et al, 2016). Notably, time-perception tasks implicate the AIC (see Gili et al, 2018). Timing has been related to the metastability of cortical networks, something that is hypothesized to be dynamically “adjusted” by the PCC (Leech and Sharp, 2014).…”

Brain Functional Connectivity Changes During Learning of Time Discrimination

“…Perception of time, which is one of the most vital functions of the brain (internal experience of time), is an abstract concept that is created based on the information recorded in the brain (internal and external senses in addition to memory) with the help of a network of its regions. Of course, each region may refer to a different aspect of time ( Buzsáki & Llinás, 2017 ; Coull & Droit-Volet, 2018 ; Gili, Ciullo, & Spalletta, 2018 ; Matthews & Meck, 2016 ; Nani et al, 2019 ).…”