Figure 4. Occurrence of late-E abdominal (AbN) activity is correlated with alterations of cranial respiratory motor outflow patterns.

At 7% CO₂, late-E AbN bursts were followed by increased amplitude (A) and advanced onset (B) of HN bursts. Black bars show cycles that were preceded by late-E AbN and grey bars, cycles that were not. C, representative CTAs show an average of 26 HN bursts (black) that were preceded by late-E AbN bursts (grey), and 24 cycles that were not. Time 0 marks onset of inspiration on PN. At 7% CO₂, late-E AbN bursts correlated with advanced onset (D) of following cVN burst and advanced offset of post-inspiratory (post-I) activities (E) of the preceding cVN bursts. F, representative CTAs were compiled from 20 cVN bursts (black) that were preceded by late-E AbN bursts (grey) and 30 that were not. All values represent mean ±s.e.m. (error bars).