Project: Interactions between auditory and limbic brain areas in tinnitus patients

Interactions between auditory and limbic brain areas in tinnitus patients

This is a summary of the request.

Tinnitus is a prevalent hearing disorder that affects millions of people and has a severely disabling impact on life in about 1-3% of the general population. It is characterized by the perception of sound in the absence of any external sound sources. An increasing amount of evidence suggests that tinnitus is generated as a result of pathological spontaneous activity in the brain. In addition to auditory brain regions, the limbic system that processes emotions is thought to be involved in the underlying mechanism. Neuroimaging studies on tinnitus have so far mainly focused on classical auditory brain centers only, but have not addressed the functional relationships with other brain areas, like the limbic system.

The current proposal is the first to use functional magnetic resonance imaging (fMRI) to investigate the auditory and limbic areas in tinnitus patients by means of innovative analysis methods: independent component analysis and connectivity analysis. These methods permit the assessment of functional interactions between brain areas. Because they do not rely on the presentation of external sound stimuli and are able to study inherent spontaneous activity of the brain, they offer a unique opportunity in the context of a disorder like tinnitus, which is generated intrinsically.

The study will include tinnitus subjects and matched controls. Functional MRI experiments will be performed using novel paradigms that include the presentation of a variety of sound stimuli as well as so-called resting state measurements. The analysis of the fMRI data will focus on the primary hypothesis that the interaction between the limbic and the auditory system is abnormal in tinnitus patients. The outcome of this study is expected to be of key importance to our understanding of tinnitus.