Figure 7. Changes in inspiratory rib motion during the application of force on the central tendon.

Data obtained in a representative animal after section of the C5-C7 dorsal roots. A, traces of axial rib motion (cranial motion upward) and parasternal intercostal and external intercostal EMG activity during two control unmanipulated breaths and a breath during which force was applied. The application of force induced an increased inspiratory cranial motion of the rib and a small reduction in external intercostal inspiratory EMG activity. B, relationship between force and inspiratory rib motion. ^, control unmanipulated breathing; •, single manipulated breaths.