EI Balance Controls Brain Synchrony

How does the brain switch between the synchronized rhythms of sleep and the scattered activity of waking? Kuroki and Mizuseki introduce the EI-Kuramoto model, which divides neural oscillators into excitatory (attractive) and inhibitory (repulsive) populations with four independently tunable interaction strengths, and shows through simulation and theory that just three collective states emerge: synchronized, bistable, and desynchronized. The bistable state — where synchrony spontaneously rises and falls in cycles — arises when cross-population interactions satisfy a specific multiplicative balance condition, revealing that inhibitory strength is the key variable that moves the system across all three regimes. Reference: Kuroki & Mizuseki (2025) "Excitation–Inhibition Balance Controls Synchronization in a Simple Model of Coupled Phase Oscillators" Neural Computation. https://doi.org/10.1162/neco_a_01763