Fig. 1.

Stimulus definition. A, The unitary excitatory conductance transient with a fast AMPA phase, injected according to Equation 1, and a much slower NMDA phase, injected with the voltage dependence described by Equation 2. B, The fraction of commanded NMDA conductance, which is unblocked, as a function of membrane potential F(V) = 1/[1 + K₁exp (−K₂V)] (see Eq. 2 and Materials and Methods). C, Diagrammatic representation of the model used to simulate concerted or synchronized inputs. See Materials and Methods for details.