Interaction of two chemoreflex loops in determining ventilatory stability

  • Zbigniew L. Topor
  • Konstantinon Vasilakos
  • John E. Remmers


A realistic model of the human ventilatory controller during sleep is presented. The model consists of two chemoreflex feedback loops (central and peripheral) each with its own delay and gain. An initial stability analysis of the resultant model produces a thumb shape region of stability for the steady state solution. Changes in cerebral blood flow in the model had profound changes in the shape of the region of the stability. Increasing the gain of either the central or the peripheral loop yielded periodic solutions consistent with observed data from humans. The model provides a new tool for understanding human ventilation during sleep. The interaction of the two loops produces complex dynamics. Understanding these dynamics will assist in the treatment of sleep-disordered breathing.