Decision time with only AMPA at recurrent synapses (c′ = 0%). A, A sample time course with very fast dynamics (t = 0 is stimulus onset). μ₀ = μ*₀ + 15 Hz, where μ*₀ is the value of μ₀ when the saddle point is just created. Bottom horizontal bar denotes the duration where the firing rates are indistinguishable; trajectory lies near the stable manifold of the saddle point. B, Reaction time as a function of μ₀ − μ*₀. Note that reaction times longer than 200 ms can hardly be realized even with parameter fine-tuning. Error bars indicate SD.