The cerebellar (para)flocculus: A review on its auditory function and a possible role in tinnitus.

The cerebellum is historically considered to be involved in motor control and motor learning. However, it is also a site of multimodal sensory and sensory-motor integration, implicated in auditory processing. The flocculus and paraflocculus are small lobes of the cerebellum, in humans located in the cerebellopontine angle. The last two decades, both structures have been a subject of interest in hearing loss and tinnitus research. The current review summarizes insights on the auditory function of the (para)flocculus and its contribution to hearing loss and tinnitus. This leads to the hypothesis of a feedback loop between the paraflocculus and the auditory cortex. Disruption of this loop may be instrumental in both maintaining tinnitus and reducing tinnitus. Although the research mostly has been performed in animals, the implications in humans are also discussed. If the (para)flocculus indeed comprises an auditory function and is part of a tinnitus-mechanism, this would potentially open up new treatment options that involve direct intervention at the (para)flocculus.