Coherence patterns in neural fields at criticality

Phase synchronization is a mechanism that plays a crucial role for information processing in the brain, and coherence is one of methods that are used to evaluate pairwise degree of phase synchronization. Coherence is also an important measure for examining brain functions because it can indicate communication and cooperation among neurons. In this work, we study the coherence patterns of spontaneous activity in the neural field model at criticality, which is a region where a second order phase transition occurs. The results are summarized as follows. First, at high frequency bands, the system outside the critical regime cannot communicate via phase synchronization at all. Second, the dynamical coherence patterns in the critical regime show switching between high and low coherent states. Finally, we found that in a very brief period of time, there is the high broadband coherence between some pairs of spatial points. This phenomenon can be observed only in the critical regime.