Transcutaneous auricular vagus nerve stimulation in the treatment of depression

Abstract Depression is a highly prevalent disorder with unsatisfactory treatment options. Recently, transcutaneous auricular vagus nerve stimulation (taVNS) has demonstrated great potential in the treatment of depression. In this chapter, we first summarize the results of clinical studies on the treatment effect of taVNS on depression. Then, we pose several hypotheses on the mechanism of taVNS treatment of depression, including modulating the activity and connectivity of key brain regions involved in depression and mood regulation, inflammation, hippocampal neurogenesis, and the microbiome-brain-gut axis. Finally, we outline current challenges and future directions of taVNS treatment of depression.