CNS somatosensory-auditory interactions elicit or modulate tinnitus

Abstract

Evidence has accumulated linking clinical tinnitus to the somatosensory system. Most clinical tinnitus patients can change the psychoacoustic attributes of their tinnitus with forceful head and neck contractions. The significance of such somatic modulation of tinnitus was assessed by testing non-clinical subjects. Like clinical tinnitus patients, about 80% of non-clinical subjects who had ongoing tinnitus at the time of testing (whether or not they had been previously aware of it) could modulate their tinnitus with head and neck contractions. Almost 60% of those with no tinnitus at the time of testing could elicit a tinnitus-like auditory percept with head and neck contractions. Because similar results were found in the profoundly deaf, we conclude that somatosensory-auditory interactions within the central nervous system account for most, if not all, somatic modulation of tinnitus as well as the development of auditory percepts with somatic testing. Other observations implicate the muscle spindle as initiating the neural activation that ultimately modulates the central auditory pathway, including the dorsal cochlear nucleus. Somatic influences upon auditory perception are not limited to tinnitus subjects but are a fundamental property of the auditory system.

Somatic Tinnitus

“…The identification of a somatic origin for her tinnitus thanks to the matching of self-reported history and modulation in the same somatic regions helped in addressing this patient to multidisciplinary somatic evaluation and treatment. Furthermore, the characteristics of tinnitus modulation found in this patient are consistent with what reported in the literature by some authors 32,33,41,42 . TMJ maneuvers induced an increase in tinnitus loudness, while NECK maneuvers induced a decrease of loudness.…”

“…This case demonstrates that tinnitus modulation can be found even when no somatic disorder is present; in fact, somatic modulation of tinnitus is a widespread condition that can be present with or without underlying somatic disorders 31,40 . Furthermore, as previously discussed, several authors reported a large capability of somatic tinnitus modulation in multiple patient series ranging between 65.3% and 83.3% 32,35,[41][42][43]45,47,61,65 . In this patient, the negative history for self-reported somatic disorder suggests caution while taking into account a somatic origin for his tinnitus.…”

“…Levine 42 described this phenomenon as a "fundamental characteristic of tinnitus", like its auditory and affective attributes. Somatic modulation has been reported in approximately two-thirds of tinnitus patients 35,43 ; other studies revealed tinnitus modulation in 85% 45 TMJ is the most common affected region in patients with somatic tinnitus.…”

“…Tinnitus can be evoked or modulated by inputs from the somato-sensory, somato-motor and visualmotor systems in some individuals [31][32][33][34][35][36][37][38][39] . This means that the psychoacoustic attributes of tinnitus (loudness and pitch) might change-though often only temporarilyfollowing external stimuli, such as the forceful muscle contractions of head, neck and limbs 31,[40][41][42][43][44] , orofacial movements 45 , eye movements in the horizontal or vertical axis 46,47 , pressure on myofascial trigger points 48,49 , cutaneous stimulation of the hand/fingertip region 50 , and of the face 43 ; electrical stimulation of the median nerve and hand or finger movements 51 . Modulation of tinnitus represents a good example of central integration in the central nervous system, following interactions between auditory and somatosensory afferents occur as early in the auditory pathways as in the cochlear nucleus, at the site of convergence of the projections from the auditory nerve and trigeminal and dorsal column ganglia and brain stem nuclei.…”

Effects of sleep bruxism related tinnitus on quality of life

“…[14,[17][18][19] Although the exact mechanism of tinnitus has not been discovered, it has been proposed that neural plasticity especially somatosensory inputs to the cochlear nucleus cause it. [20,21] On the other hand, the association of tinnitus and SB is not clear. Camparis et al [22] found that tinnitus frequency was higher in patients with SB and chronic facial pain.…”