Activities of the phrenic and vagus nerves in the mouse during E, after administration of M, and in G. Note that, following administration of 3.0 μM of M, the frequency of neural bursts increased, but ∫Vag remained linked to the ∫Phr. Small, high-frequency oscillations on records of ∫Phr activity and higher amplitude spies on records of vagal activity both represent electrocardiograms.