Figure 4. Measures of the change in airway pressure (±s.d.) associated with whole XII nerve and medial XII branch preparations in the stimulus and no-stimulus conditions across the volume range.

The area below zero corresponds to the airway volumes at which stimulation resulted in airway dilatation. * Significant differences between the airway pressures obtained with whole XII vs. medial XII branch stimulation (P < 0.05) at a given airway volume. †Significant differences between the zero pressure and stimulus airway conditions at a given airway volume. Note that medial branch stimulation (i.e. tongue protrudor activation) resulted in significant airway dilatation at the lowest airway volumes whereas whole nerve stimulation did not.