Body of Research

Through a systematic review of Medline and Embase databases, with the inclusion of four preclinical and five clinical studies on Trigeminal Nerve Stimulation (TNS) and transcutaneous auricular Vagus Nerve Stimulation (tVNS), Shiozawa et. al. concluded that TNS and tVNS improve treatment of particular neuropsychiatric disorders such as depression. See the details of the study that shows promising (even though mixed) results at SciELO Brasil.

Reference: Shiozawa P, Silva ME, Carvalho TC, Cordeiro Q, Brunoni AR, Fregni F. Transcutaneous vagus and trigeminal nerve stimulation for neuropsychiatric disorders: a systematic review. Arq Neuropsiquiatr. 2014 Jul;72(7):542-7. doi: 10.1590/0004-282x20140061. PMID: 25054988.