Fig. 5. Ensemble averages of electromyographic (EMG) activity of the parasternal
portion of the internal intercostal muscle. The bursting pattern is consistent
in uncoupled breath averages, indicating a clear inspiratory function for this
muscle. The bursting is much more variable in uncoupled stride averages and
almost undetectable in the average across all dogs (E), indicating a variable
or sporadic locomotor function that may be different in each dog. Samples are
from four dogs (A—D), and the average across four dogs (E), with
ventilatory (bold lines) and acceleration (thin lines) traces to reveal
relationships to breath and stride (F). IF indicates ipsilateral forelimb
support and CF contralateral forelimb support in the footfall bars at the
bottom. All traces are on the same time scale. Exp., expiration; Insp.,
inspiration.
