From acute to chronic tinnitus, which signatures in brain activity make tinnitus persistent?

• Applicant: Dr. Nadia Müller-Voggel
• Subject Area: Personality Psychology, Clinical and Medical Psychology, Methodology ; General, Cognitive and Mathematical Psychology
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 334628700

Tinnitus is an acoustic phantom perception, which causes severe problems in daily life of millions of people worldwide. So far tinnitus is insufficiently understood and no effective therapy is available. It is thus of great importance to systematically clarify the still unsolved questions in tinnitus. So far it is widely accepted that tinnitus is initiated by peripheral hearing loss that triggers neuroplastic changes along the ascending auditory pathway. This leads to a disinhibition in the auditory system, and in particular in the auditory cortex. In line with that it has been shown that oscillatory activity in the auditory system is altered in tinnitus patients and that normalizing abnormal oscillatory activity reduces tinnitus. Beyond the abnormalities within the auditory pathway, multiple non-auditory networks, related to attention, emotion or memory functions, are involved in tinnitus. Thus, both, the disinhibition in the auditory system, and in particular in the auditory cortex, and non auditory networks contribute to tinnitus. Current models on tinnitus, however, cannot answer various crucial questions: Why does tinnitus become chronic in some patients and in some patients it disappears without specific intervention? Can we find signatures in neuronal activity that separate tinnitus developing and non developing individuals before tinnitus onset? Can we identify factors that prevent tinnitus chronification in the acute phase of tinnitus development? These questions were virtually not addressed as human tinnitus research typically focuses on studies with patients, not developing, but already suffering many years from chronic tinnitus. With the present proposal I aim at clarifying exactly these questions by disclosing the role of auditory markers, non auditory markers and their interaction during development and chronification of tinnitus. Therefore, brain activity will be recorded with Magnetoenzephalography in the course of tinnitus development and chronification in different settings. Neurophysiological signatures associated with pathological auditory and non-auditory activity related to tinnitus will be identified according to the different phases of tinnitus development and chronification. This will give crucial insights into when and how tinnitus becomes persistent, identify risk factors for the development of tinnitus and disclose neurophysiological processes leading to resilience against tinnitus chronification. Based on that it will be possible to systematically develop new therapies.

• DFG Programme: Independent Junior Research Groups
• Cooperation Partners: Professor Dr. Hajo Hamer; Privatdozent Dr. Stefan Rampp; Professor Dr. Holger Schulze