Optimal signal amplification in globally coupled bistable oscillators: The role of weight between positive and negative couplings

Abstract

Recently, it was revealed that uniformly positive and negative couplings perform complementary roles in the signal amplification of coupled bistable oscillators. However, the coupling weights between oscillators are usually nonuniform due to adaptivity in many nonlinear systems. For this reason, we introduce a weight ratio of positive and negative couplings and investigate how it affects the response of globally coupled bistable oscillators to a subthreshold signal. We show that the weight ratio can significantly optimize the system response to the subthreshold signal compared to the case of uniform couplings. Finally, we propose a reduced model and compare its analytical approximations with the numerical results.