Independent Noise Synchronizing Networks of Oscillator Networks

Oscillators coupled in a network can synchronize with each other to yield a coherent population rhythm. If multiple such networks are coupled together, the question arises whether these rhythms will synchronize. We investigate the impact of noise on this synchronization for strong inhibitory pulse-coupling and find that increasing the noise can synchronize the population rhythms, even if the noisy inputs to different oscillators are completely uncorrelated. Reducing the system to a phenomenological iterated map we show that this synchronization of the rhythms arises from the noise-induced phase heterogeneity of the oscillators. The synchronization of population rhythms is expected to be particularly relevant for brain rhythms.