Figure 6. Model simulations of neuronal activity during normocapnia and hypercapnia.
Active expiration emerges in model activity following an increase in chemosensitive drive to the late expiratory population (late-E) of the parafacial respiratory group (pFRG). The baseline model activity (Panel A) transforms to include late-expiratory bursts (Panel B) when the chemosensitive drive to late-E is increased by 33%. The transformation of the respiratory pattern during the late expiratory phase is emphasized by the orange shaded boxes. Other abbreviations – aug-E: augmenting expiratory population; post-I (GABA): GABAergic post-inspiratory population; post-I (Gly): glycinergic post-inspiratory population; early-I: early inspiratory population.