Hearing Loss-induced Tinnitus Alleviation by Cortical Map Reorganization

Tinnitus, a constant ringing in the ear, is a major cause of disability in activities of daily living. In particular, hearing loss-induced tinnitus is often associated with comorbidities such as anxiety, deficits in attention, insomnia, and depression; all of which severely affect quality of life. Currently, there are only limited therapeutic treatments of which effect is even uncertain until now. Our previous research implicates that enhancing sensory inputs in a hearing loss area of the auditory cortex can alleviate tinnitus through cortical map reorganization (or expansion). Yet, this tenet has not been empirically tested. Here, we aim to directly test whether enhancing synaptic drive through cortical stimulation can rewire the network of sensory neurons and thereby alleviate hearing loss-induced tinnitus. We have developed a graphene-based multichannel electrode that integrates thin and flexible electronics into an electrocorticography (ECoG) array. This technology permits the simultaneous detection of cortical activities on multiple sites for diagnostic purpose and delivers rehabilitative electrical pulses for treatment. Our preliminary data demonstrate that the graphene ECoG can access cortical maps in a time- and labour-efficient manner. Furthermore, long-term reorganization of cortical map is observed when a sensory stimulus is paired with electrical stimulation at the cortical surface. Here, we propose that the reorganization of cortical map can alleviate tinnitus through our graphene-based therapeutic interface. A successful implementation would immediately offer applications in other brain map-related diseases such as schizophrenia, epilepsy, depression, and Parkinson’s disease.