Because the initial diagnosis and evaluation of treatment effects cannot be objectified easily, the treatment goals are aimed at symptomatic relief relying on patients’ subjective symptom reports in the majority of cases. The absence of standardized single gold-standard treatment for tinnitus thus necessitates combinations selleck chemical Dorsomorphin of treatment strategies or developments of novel treatment modalities.With the development of the idea that the unified tinnitus percept is an emergent network property resulting from activity in multiple, parallel, partially overlapping but separable networks [13] encompassing both auditory and nonauditory brain areas [14, 15], new treatments are being developed, including both pharmacological [16] and neuromodulatory approaches [17].

Over the last decade, noninvasive neuromodulations such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), transcutaneous electrical nerve stimulation, and neurofeedback have been used, as well as invasive neuromodulation techniques. These include implantable cortical electrodes on the auditory and the dorsolateral prefrontal cortex (DLPFC), as well as subcutaneous occipital nerve stimulation, and deep brain stimulation [18], especially for cases of intractable tinnitus. Of these neuromodulation methods, tDCS might become a clinically useful noninvasive neuromodulation technique for tinnitus suppression due to its low cost, easy, painless application, and its longer residual inhibition than TMS. tDCS delivers low direct currents (0.

5�C2mA) via scalp electrodes to the cerebral cortex that result in the modulation of cortical excitability for variable periods outlasting the stimulation period [19]. A part of this current is shunted through the scalp and the rest flows into the cerebral cortex, thereby increasing or decreasing cortical excitability in the brain regions to which it is applied depending on the polarity of the stimulation [20]. Currently, tDCS is usually applied through 2 surface electrodes, one serving as an anode and the other AV-951 as a cathode. Anodal tDCS typically has an excitatory effect on the underlying cerebral cortex by depolarizing neurons, while cathodal tDCS decreases cortical excitability by induced hyperpolarization [21]. This excitability changing effect of tDCS is typically maintained for an hour or longer after a single session of sufficiently long stimulation duration [21�C24]. tDCS has been applied for treating major depression [25�C27] and chronic pain [28, 29] with relatively promising outcomes.