Source: Brain Stimulation. 14(1):113-128, 2021 Jan-Feb.
Authors: Lefebvre-Demers M; Doyon N; Fecteau S
BACKGROUND: Patients with tinnitus often have poor quality of life, as well as severe anxiety and depression. New approaches to treat tinnitus are needed.
OBJECTIVE: Evaluate the effects of non-invasive neuromodulation on tinnitus through a metaanalysis and modeling study. The main hypothesis was that real as compared to sham neuromodulation that decreases tinnitus will modulate regions in line with the neurobiological models of tinnitus.
METHODS AND RESULTS: The systematic review, conducted from Pubmed, Cochrane and PsycINFO databases, showed that active as compared to sham repetitive transcranial magnetic stimulation (rTMS) reduced tinnitus, but active and sham transcranial direct current stimulation did not significantly differ. Further, rTMS over the auditory cortex was the most effective protocol. The modeling results indicate that this rTMS protocol elicited the strongest electric fields in the insula. Also, rTMS was particularly beneficial in women. Finally, the placebo effects were highly variable, highlighting the importance of conducting sham-controlled trials. CONCLUSION: In sum, neuromodulation protocols that target the auditory cortex and the insula may hold clinical potential to treat tinnitus.