The nucleus tractus solitarius (NTS) in the medulla integrates afferent inputs from the cervical vagus (X, e.g. aortic arch baroreceptors, lungs), glossopharyngeal nerve (IX, e.g. carotid baroreceptors), and auricular branch of the vagus (ABV). NTS input to higher brain regions processing different aspects of pain is thought to underlie the anti-nociceptive effects of vagus nerve stimulation (VNS). N.b. SpV = trigeminal nucleus, PB = parabrachial nucleus, LC = locus ceruleus, PAG = periaqueductal gray, hyp = hypothalamus, amyg = amygdala, thal = thalamus, ins = insula, ACC = anterior cingulate cortex, PFC = prefrontal cortex, S1 = primary somatosensory cortex.