2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/96757We study a simple map as a minimal model of excitable cells. The map has two fast variables which mimic the behavior of class I neurons, undergoing a sub-critical Hopf bifurcation. Adding a third slow variable allows the system to present bursts and other interesting biological behaviors. Bifurcation lines which locate the excitability region are obtained for different planes in parameter space.7 pages, 3 figures, accepted for publicationNeurons and CognitionDisordered Systems and Neural NetworksChaotic DynamicsBiological Physicstext