Decoupling Stereotyped Dynamics from Criticality in Simple Neural Networks

Stereotyped spatiotemporal dynamics—where spontaneous activity exhibits highly repeated patterns—have been observed in neural systems exhibiting scale-free neuronal avalanches. While stereotyped dynamics are associated with avalanche criticality, it remains unclear whether critical tuning is necessary for the emergence of such spatiotemporal stereotypy. Here, we investigate how stereotyped dynamics, network structure, and criticality interact with each other by simulating spontaneous activities in two types of networks, randomly connected and a spatially organized network with local excitation and lateral inhibition (LE/LI). We found that emergence of stereotyped dynamics is determined by heterogeneity of degree of nodes in the networks but not criticality. Moreover, LE/LI networks show stronger stereotyped dynamics than randomly connected networks, suggesting that structured connectivity could promote the formation of recurring low-dimensional activity patterns. Together, these results suggest that stereotyped dynamics can arise from structural constraints by introducing a simple connectivity rule rather than critical tuning.