Tinnitus as a network problem – plasticity in anatomical and functional connectivity
Final Report Abstract
Tinnitus is the phantom perception of sound when there is no external auditory input. This sound is mostly perceived as a whistling, buzzing or hissing in the ear. Chronic tinnitus – the permanent phantom perception – currently affects 10-20% of the population but no reliable treatment has been found so far. The funded study was conducted at Georgetown University (Laboratory of Integrative Neuroscience and Cognition of Prof. Dr. Josef Rauschecker) and investigated underlying neuroplastic changes in anatomical and functional connectivity related to the tinnitus perception itself and related to tinnitus distress (e.g. emotional distress, anxiety and depression) and cognitive impairments resulting from chronic tinnitus. The first study demonstrated increased grey matter volume in middle frontal gyrus in tinnitus patients compared to control participants. Further, increased cortical thickness in middle frontal gyrus was associated with higher MOCA scores in controls and lower MOCA scores in tinnitus patients. In addition, increased tinnitus distress was correlated with increased cortical thickness in the precuneus. The second study provided evidence of associations between general cognitive abilities and resting state functional connectivity in the default mode network, the precuneus, the superior parietal lobule, orbital cortex and the supramarginal gyrus in tinnitus patients. Moreover, tinnitus distress correlated with resting state functional connectivity between the precuneus and the lateral occipital complex. The third study showed significantly increased fiber density (i.e. changes in tissue microstructure) in the fornix in tinnitus patients compared to control participants. In order to identify suitable target regions for neuromodulatory approaches or designing cognitive behavioral therapy strategies in tinnitus, understanding its pathophysiology is of crucial importance. Thus, the present findings provide useful insights into neural alterations in tinnitus patients related to tinnitus distress and cognitive functions and highlight the roles of middle frontal gyrus, precuneus as well as the default mode network and the fornix. These results may be relevant in order to advance treatment options for tinnitus or evaluating the efficacy of tinnitus interventions.
Publications
- (2022). Neuroanatomical alterations in middle frontal gyrus and the precuneus related to tinnitus and tinnitus distress. Hearing Research, 108595
Rosemann, S., & Rauschecker, J. P.
(See online at https://doi.org/10.1016/j.heares.2022.108595)
