Patterns of Tinnitus and Hearing Loss Secondary to Blast Injury

This three-year study proposes to recall Marine and Navy participants of the Marine Resiliency Studies, who were deployed and subject to blast-induced TBI for permission to access past and current audiograms given by the DoD and DVA, and to participate in phone interviews and complete on-line questionnaires, among consenting participants,200 individuals divided among four groups will be invited for on-site evaluations. The study groups will be Group 1Blast-exposed during deployment with post concussive symptoms PCS, new onset and persistent tinnitus Group 2Blast-exposed PCS, no tinnitus Group 3 No blast-exposure during deployment, but new tinnitus Group 4 No blast exposure, no tinnitus. The onsite evaluations will consist of a magnetoencephalography MEG scan, hearing tests, standard MRS interviews, neurocognitive tests and questionnaires, and tinnitus questionnaires. By comparing subjects with tinnitus and those without, we hope better characterize the symptoms of blast-related tinnitus when compared to tinnitus from other causes such as falls or chronic noise exposure. We hope to develop better ways make an objective test, or diagnosis for tinnitus in blast versus non-blast exposed individuals with tinnitus onset. Thus our ultimate goal is to characterize the areas of the brain specifically associated with tinnitus.