This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
VNS works by 
Select and explain. 
A. deep brain stimulation, B. vagal nerve stimulation, C. magnetic stimulation, D. convulsion production
B: vagal nerve stimulation
Answer: B: vagal nerve stimulation 
Explanation: Vagus nerve stimulation * Electrical stimulation of left vagus nerve * Stimulation of raphe nucleus and locus cereleus * Release of norepinephrine and serotonin * Side effects * Voice alteration Ref. kaplon and sadock, synopsis of psychiatry, 11 th edition, 1075