Critical neuronal avalanches arise from excitation-inhibition balanced spontaneous activity

Neuronal avalanches are sequences of neural activations exhibiting scale-invariant statistics, indicative of critical dynamics. Theoretical studies proposed that the balance between excitation (E) and inhibition (I), along with neuromodulation, are key factors influencing this critical behavior. Here, we performed in-vivo studies to investigate the role of E and I neurons in generating neuronal avalanches in the optic tectum of zebrafish larvae. For this, we used double-transgenic zebrafish larvae expressing cell-type-specific fluorescent proteins and GCaMP6f, combined with immunostaining and selective-plane illumination microscopy to monitor spontaneous neuronal activity and neurotransmitte