A method for modulating a nerve within a body of a patient includes generating a single signal comprising an electrical impulse, contacting an interface with an outer skin surface of a patient and delivering the electrical impulse from an electrode through the interface and the outer skin surface of the patient to a vagus nerve, thereby modulating the vagus nerve. The electrical impulse may comprise bursts of pulses with a silent intra-burst interval between each of the bursts based on the single signal, wherein each of the bursts has a frequency of about 5 Hz to about 100 Hz and each of the pulses has a duration from about 50 microseconds to about 1000 microseconds. The electrode may be spaced from the interface by a distance of about 0.25 to about 4 times an outer dimension of the interface.