Abstract

Recent functional brain imaging studies in humans suggest that the neural generator(s) for tinnitus may reside in the central nervous system and involve both auditory as well as nonauditory centers. The contribution of nonauditory centers in the pathogenesis and regulation of tinnitus is reinforced by studies showing that many patients have somatic tinnitus whereby movements and manipulations of the eyes, head, neck, jaw, and shoulder can modulate the loudness and pitch of their tinnitus. In most cases, the maneuvers lead to increases in tinnitus loudness or pitch rather than decreases. Our results indicate that most tinnitus patients experience only a modest change in loudness or pitch when performing these maneuvers. However, some patients report that these maneuvers significantly modulate the loudness or pitch, sometimes by a factor of 2 to 3. The high prevalence of somatic tinnitus serves to illustrate the complex multimodal interactions that exist between the auditory pathway and other sensory-motor systems innervating the head, neck, shoulders, and eyes.