Passive membrane properties of the stellate neuron models.

Input resistance (Ri) was defined as the ratio of the steady-state voltage change in response to positive (��+��) or negative (��?��) current injection from the resting membrane potential. Monoexponential fits to the initial voltage response were used to obtain the membrane time constant (��m). The sag ratio is calculated as the ratio of the peak hyperpolarization divided by the steady-state hyperpolarization for the negative current injection. Parameter estimates from the stochastic models were determined from an average of 5 simulations. Errors are the standard deviation.