Neural plasticity, hearing loss and tinnitus: changes in tonotopic maps of the auditory cortex

With an increased life expectancy and an ageing population, age-related dysfunctions are becoming more prevalent. The most widespread of all sensory impairments in an ageing population is hearing loss, which is characterized by a loss of sensitivity of the peripheral hearing organ, the inner ear. This peripheral hearing loss is associated with less sensory input available to the brain. Animal research has shown that peripheral hearing loss may cause widespread plastic changes in the brain. Peripheral hearing loss is often associated with tinnitus: about 30% of the people with hearing loss also develop tinnitus. It has been suggested previously that tinnitus and tonotopic reorganisation are causally related. Such cortical reorganisation presumably contributes to the impaired communication skills experienced by humans with hearing loss. With an increasing demand for active participation of the elderly in society, it is crucially important to understand the neurobiological consequences of hearing loss and tinnitus.



The current study employs functional magnetic resonance imaging (fMRI) to investigate the relation between peripheral hearing loss, tinnitus and cortical reorganization. In particular, it aims to map the topographic representation of sound frequency, referred to as tonotopic maps, and how these change as a consequence of tinnitus and hearing loss. It also aims to investigate whether the type of hearing loss is related to the degree of reorganisation.

No longitudinal design; just one time-point

fMRI measurements while listing to sound fragments.