Figure 6. Effects of dorsal root section.

Relationships between force and peak parasternal intercostal (A) and external intercostal (B) EMG activity before (•-•) and after (^ - - ^) section of the C5-C7 dorsal roots in a representative animal. EMG activity is expressed as percentage change relative to the activity recorded during resting unmanipulated breathing. Sectioning the dorsal roots abolished the reduction in parasternal intercostal activity (no dashed line is shown) and attenuated the reduction in external intercostal activity.