Vanneste, S., Focquaert, F., Van de Heyning, P., & De Ridder, D. (2011). Different resting state brain activity and functional connectivity in patients who respond and not respond to bifrontal tDCS. Experimental Brain Research, 210, 217-227.

Tinnitus is an ongoing phantom percept. It has been demonstrated that bifrontal transcranial direct current stimulation (tDCS) can reduce tinnitus. In this study, one group of patients reported a substantial improvement in their tinnitus perception, whereas another group described minor or no beneficial effect at all. The objective was to verify whether the activity and connectivity of the resting brain is different for people who will respond to bifrontal tDCS for tinnitus in comparison with non-responders. Responders to bifrontal tDCS seem to differ in resting brain activity compared to nonresponders in the right auditory cortex and parahippocampal area. They also havea different functional connectivity between DLPFC and, respectively, the sgACC and parahippocampal area. These connectivities might explain the suppression effect for both tinnitus loudness and tinnitus related distress.