The AudioNotch Tinnitus Treatment Blog

TMS Tinnitus

Written by AudioNotch Team on March 27, 2014

TMS, as it is colloquially referred to (or Repetitive Transcranial Magnetic Stimulation, which is the proper term) has recently been investigated as a possible treatment avenue for tinnitus. A lot patients get excited about TMS & tinnitus, but the results have not been good. People are attracted to TMS because it’s noninvasive (basically just a magnet held over your head) and thus doesn’t really appear to have any significant complications with use. It’s been used in depression as well, and the logic is that you could target the affected region of the brain non-invasively. Unfortunately, a new study in 2014 has come out and reaffirmed its lack of efficacy:

An increasing amount of studies apply repetetive transcranial magnetic stimulation (rTMS) to treat chronic tinnitus, yet the neurophysiological impacts have remained largely obscure. Several studies show that endogenous brain rhythms may be enhanced via diverse brain stimulation techniques applying rhythmic stimulation. Here, we investigated in normal hearing participants whether application of rTMS (left auditory cortex) with an individualized alpha frequency was capable of increasing alpha activity in stimulated auditory regions in a sustained manner. Behavioral intensity discrimination performance worsened for the rTMS group as compared to Sham. Electroencephalography (EEG) data, however, clearly show that this functional inhibition is not accompanied by increases of auditory cortical alpha. Even though more pronounced power reductions for the rTMS group were observed at slower frequencies (delta to theta range) at stimulated and other sites of the left hemisphere, they were unrelated to behavioral changes. Our results also strongly suggest that the amount of power modulations at these slower frequencies is strongly dependent on pre-rTMS power, thus supporting current state-dependency notions. Strong relationships to behavioral changes were in particular observed for anterior cingulate cortex (ACC) beta power and posterior cingulate cortex (PCC) beta connectivity. Moreover, these beta band measures were strongly inter-related and when viewed together specifically sensitive to behavioral changes in the rTMS group. We conclude that currently alpha frequency rTMS is not a promising avenue for the treatment of chronic tinnitus and that beneficial effects could be mediated via nonauditory systems. Our study argues for the value of combined EEG-TMS studies when investigating the impacts of rTMS. Hum Brain Mapp 35:14–29, 2014. © 2012 Wiley Periodicals, Inc.