ABVN Phase 2-Studying the Effect of Stimulation on the Auricular Branch of the Vagal Nerve

Electrical stimulation electrodes will be placed on the ear with the intensity of the current being increased by 10 percent every 60 seconds, the subject will grade the intensity of the current on a scale of 0-10. Increasing of the current will occur until the subject reports a comfortable level. Once the target level has been achieved the stimulation will be delivered for 2 minutes.

"Subjects will undergo the following procedures to stimulate the vagus nerve.~* Cough: 6 to 8 forceful coughs~* Cold stimulus: a washcloth soaked in ice water will be placed on the face for 10 seconds.~* Carotid massage~* Gagging: a tongue depressor will be inserted for 10 seconds into the mouth touching the back of the mouth.~* Valsalva maneuver: subjects will will be asked to bear down as if they were having a bowel movement. They will be asked to blow through a mouthpiece that is hooked to a machine that measures how hard they are blowing.~* Eating: Subjects will be asked to drink water ( 8oz or 1 cup) or/ and Ensure Original ( 8 oz or 1 cup) that has 220 calories after fasting overnight to see that effect on vagal activity during eating."