The phenomena of selective response of an excitable system to external puls
e stimulation relating to interneuron communication and information process
ing problems are discussed. Subthreshold dynamics of the FitzHugh-Nagumo-li
ke excitable system modeling of a neuron with the synaptic input is investi
gated. It is shown that the system response on various incoming information
messages can be described by one- and two-dimensional linear and nonlinear
point maps. Nonlinear integrating and resonant properties of the system ar
e analyzed.