An Exploratory Study of Bimodal Electro-Aural Stimulation Through the Ear Canals for Tinnitus

Objective: The aim of this study was to explore the potential for bimodal auditory and noninvasive electrical stimulation at the ears to alleviate tonal, somatic tinnitus that was investigated in a small preliminary trial (11 participants). Design: Auditory stimulation took the form of short “notched noise” bursts customized to each participant's tinnitus percept. Simultaneous pulsed electrical stimulation, intended to facilitate neuroplasticity, was delivered via hydrogel electrodes placed in opposite ears. Results: After a 6-week intervention period, average Tinnitus Functional Index (TFI) and Tinnitus Primary Function Questionnaire (TPFQ) scores were consistent with clinically meaningful improvements in the study population. Magnitudes and effect sizes of improvements in TFI and TPFQ are comparable to those reported in other recent bimodal therapy studies using different auditory and electrical stimulation parameters. Conclusions: Our results should be considered preliminary given the small sample size, lack of crossover data, and small subject pool. When considered alongside other recent bimodal therapy results, we do believe that there are therapeutic benefits of bimodal stimulation for tinnitus sufferers that have the potential to help some with tinnitus, with a variety of stimulation parameters and electrode placements. Supplemental Material: https://doi.org/10.23641/asha.25444546