A study to evaluate the efficacy of vagus nerve stimulation and acoustic stimuli coupling in reducing tinnitus-related distress for chronic subjective tinnitus: a randomised controlled trial (RCT).

This study is a multi-group pretest-post test, triple-blinded, randomized controlled trial (RCT) to evaluate the efficacy of available Vagus Nerve Stimulation and acoustic stimuli coupling in reducing tinnitus-related distress for three different sub-types of chronic subjective tinnitus. 60 patients will be randomly assigned to any of the three intervention groups: VNS + Matched noise, VNS + Notched noise, and Tinnitus Educational Counselling. VNS is a non-invasive transcutaneous auricular Vagus Nerve Stimulation provided using a Neurostim device at Cymba Concha of the left ear at a max comfortable level. Matched noise is a 1-octave band of white noise focused on the tinnitus frequency, and Notched noise is a white noise with a 1-octave exclusion focused on the tinnitus frequency presented at 5dB SL (re: tinnitus frequency threshold) using custom-made MATLAB code routed to an audiometer via an insert earphones. The intervention will be implemented over 3 weeks in a 3-2-1 sessions/week sequence, and outcomes will be measured at post-treatment and at an on-call 1-month follow-up.