Networks of Bistable Mutual Activation Switches

Biological decision-making is often discrete: regulatory programs tend to settle into stable “ON/OFF” regimes that persist despite molecular noise. This proposal investigates how such categorical out- comes can emerge not from isolated motifs, but from networks of interacting bistable switches. Our central hypothesis is that coupling strength g governs a tradeoff between fate diversity and coordination: weak coupling sustains multiple mixed equilibria with sizable basins of attraction, whereas strong coupling drives consensus by expanding the basins of coordinated attractors until mixed basins are swallowed. We frame this claim in the language of dynamical landscapes, where cell-level outcomes correspond to attractors and robustness corresponds to basin volume. These predictions yield measurable signatures for cell decision-making.