At least one of a plurality of disorders of a patient characterized at least in part by vagal activity innervating at least one of a plurality of organs of the patient is treated by a method that includes positioning an electrode on a vagus nerve. An electrical signal is applied to the electrode to modulate vagal activity by an amount selected to treat the disorder. In some embodiments, the disorder is gastroparesis. The signal may be a blocking or a stimulation signal. In some embodiments, the signal is selected to a) at least in part, upregulate neural activity on the vagus nerve without triggering muscular contractility, and, b) increase pancreobilliary output.