Tinnitus in migraine: an allodynic symptom secondary to abnormal cortical functioning?

Tinnitus is not a common auditory symptom in migraine. Recent research suggests that central sensitization (CS) develops in most migraneurs during the course of a migraine attack. Herein we describe 3 patients with primary headache disorders and tinnitus as their chief complaint, in whom the tinnitus intensity consistently increased during headache attacks. In headache patients, tinnitus may be related to spontaneous and aberrant neural activity at any level along the auditory axis, with abnormal reorganization processes in the auditory cortex following hearing receptor damage. We hypothesize that the tinnitus intensity increase could be an allodynic symptom related to CS, or alternatively could be associated with cortical hyperexcitability.