Assessment and Modification of the Tinnitus-Related Cortical Network

Tinnitus refers to the perception of a sound in the absence of any physical source, and it is widely believed that this phantom sound is generated in the central nervous system. Thus the activation of neuronal cell assemblies is chronically changed in patients with an ongoing tinnitus perception. We used magnetoencephalography to investigate these changes in a resting condition. There was an increase of synchronized activity in the gamma and delta frequency range together with a decrease in the α band. Manipulation of these cortical networks by means of neurofeedback therapy resulted in a reduction of tinnitus loudness and distress. In this article we review the basic research and the clinical studies conducted in our laboratory and propose a model that explains the results and helps guide future research and therapy. KEYWORDS Tinnitus - magnetoencephalography - neurofeedback - resting state