Original Research ARTICLE
Changes of oscillatory activity in pitch processing network and related tinnitus relief induced by acoustic CR neuromodulation
- 1 Institute of Neuroscience and Medicine – Neuromodulation, Research Center Jülich, Jülich, Germany
- 2 Department of Stereotactic and Functional Neurosurgery, University of Cologne, Cologne, Germany
Chronic subjective tinnitus is characterized by abnormal neuronal synchronization in the central auditory system. As shown in a controlled clinical trial, acoustic coordinated reset (CR) neuromodulation causes a significant relief of tinnitus symptoms along with a significant decrease of pathological oscillatory activity in a network comprising auditory and non-auditory brain areas, which is often accompanied with a significant tinnitus pitch change. Here we studied if the tinnitus pitch change correlates with a reduction of tinnitus loudness and/or annoyance as assessed by visual analog scale (VAS) scores. Furthermore, we studied if the changes of the pattern of brain synchrony in tinnitus patients induced by 12 weeks of CR therapy depend on whether or not the patients undergo a pronounced tinnitus pitch change. Therefore, we applied standardized low-resolution brain electromagnetic tomography (sLORETA) to EEG recordings from two groups of patients with a sustained CR-induced relief of tinnitus symptoms with and without tinnitus pitch change. We found that absolute changes of VAS loudness and VAS annoyance scores significantly correlate with the modulus, i.e. the absolute value, of the tinnitus pitch change. Moreover, as opposed to patients with small or no pitch change we found a significantly stronger decrease in gamma power in patients with pronounced tinnitus pitch change in right parietal cortex (Brodmann area, BA 40), right frontal cortex (BA 9, 46), left temporal cortex (BA 22, 42), and left frontal cortex (BA 4, 6), combined with a significantly stronger increase of alpha (10–12 Hz) activity in the right and left anterior cingulate cortex (ACC; BA 32, 24). In addition, we revealed a significantly lower functional connectivity in the gamma band between the right dorsolateral prefrontal cortex (BA 46) and the right ACC (BA 32) after 12 weeks of CR therapy in patients with pronounced pitch change. Our results indicate a substantial, CR-induced reduction of tinnitus-related auditory binding in a pitch processing network.
Keywords: tinnitus, coordinated reset neuromodulation, pitch, phantom perception, gamma band activity, electroencephalography
Citation: Adamchic I, Hauptmann C and Tass PA (2012) Changes of oscillatory activity in pitch processing network and related tinnitus relief induced by acoustic CR neuromodulation. Front. Syst. Neurosci. 6:18. doi: 10.3389/fnsys.2012.00018
Received: 23 December 2011; Accepted: 06 March 2012;
Published online: 05 April 2012.
Edited by:Jos J. Eggermont, University of Calgary, Canada
Reviewed by:Jos J. Eggermont, University of Calgary, Canada
Berthold Langguth, University of Regensburg, Germany
Sven Vanneste, University Hospital Antwerp, Belgium
Copyright: © 2012 Adamchic, Hauptmann and Tass. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits noncommercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.
*Correspondence: Ilya Adamchic, Institute of Neuroscience and Medicine – Neuromodulation, Research Center Jülich, 52425 Jülich, Germany. e-mail: email@example.com