Dynamical effects of integrative time-delay coupling.

We study coupled dynamical systems wherein the influence of one system on the other is cumulative: coupling signals are integrated over a time interval τ. A major consequence of integrative coupling is that amplitude death occurs over a wider range and in a single region in parameter space. For coupled limit cycle oscillators (the Landau-Stuart model) we obtain an analytic estimate for the boundary of this region while for coupled chaotic Lorenz oscillators numerical results are presented. For given τ we find that there is a critical coupling strength at which the frequency of oscillations changes discontinuously.