Auditory and visual 3D virtual reality therapy for chronic subjective tinnitus: theoretical framework

It is estimated that ~10% of the adult population in developed countries is affected by subjective tinnitus. Physiopathology of subjective tinnitus remains incompletely explained. Nevertheless, subjective tinnitus is thought to result from hyperactivity and neuroplastic reorganization of cortical and subcortical networks following acoustic deafferentation induced by cochlear or auditory nerve damage. Involvement of both auditory and non-auditory central nervous pathways explains the conscious perception of tinnitus and also the potentially incapacitating discomfort experienced by some patients (sound hypersensitivity, sleep disorders, attention deficit, anxiety or depression). These clinical patterns are similar to those observed in chronic pain following amputation where conditioning techniques using virtual reality have been shown both to be theoretically interesting and effectively useful. This analogy led us to develop an innovative setup with dedicated auditory and visual 3D virtual reality environments in which unilateral subjective tinnitus sufferers are given the possibility to voluntarily manipulate an auditory and visual image of their tinnitus (tinnitus avatar). By doing so, the patients will be able to transfer their subjective auditory perception to the tinnitus avatar and to gain agency on this multimodal virtual percept they hear, see and spatially control. Repeated sessions of such virtual reality immersions are then supposed to contribute to tinnitus treatment by promoting cerebral plasticity. This paper describes the theoretical framework and setup adjustments required by this very first attempt to adapt virtual reality techniques to subjective tinnitus treatment. Therapeutic usefulness will be validated by a further controlled clinical trial.