Phylogenetically-Preserved Multiscale Neuronal Activity: Iterative Coarse-Graining Reconciles Scale-Dependent Theories of Brain Function

Brain recordings collected at different resolutions support statistically distinct signatures of information processing, leading to scale-dependent theories of brain function. Here, we demonstrate that these disparate neural-coding signatures emerge from the same multiscale functional organisation of neuronal activity across calcium-imaging recordings collected from the whole brains of zebrafish and nematode, as well as sensory regions of the fly, mouse, and macaque brain. Network simulations show that hierarchical-modular structural connectivity facilitates multiscale functional coordination, enhancing information processing benefits such as a maximal dynamic range. Finally, we demonstrate that this cross-scale organisation supports distinct behavioural states across species by reconfiguring functional affiliation and temporal dynamics at the mesoscale. Our findings suggest that self-similar scaling of neuronal activity is a universal principle that reconciles scale-dependent theories of brain function, facilitating both efficiency and resiliency while enabling significant reconfiguration of mesoscale cellular ensembles to accommodate behavioural demands.