Somatic Modulation of Tinnitus: A Review and Some Open Questions.
Tinnitus modulation by movements of the temporomandibular joint, head and neck musculoskeletal
structures and the eye can be found in one to two thirds of tinnitus sufferers; unfortunately
this condition is often overlooked by otolaryngologists.
Although somatic modulation has been initially hypothesized as a fundamental characteristic of tinnitus, there is increasing evidence of a tight connection with disorders of non-auditory regions.
The structure that mostly modulates tinnitus is the temporomandibular joint, which mainly causes an increase in tinnitus loudness, followed by head and neck movements that may result in an increase or decrease of loudness and eye movements.
Besides loudness, somatic movements can also modulate tinnitus pitch and localization. Somatosensory tinnitus is a relatively new finding that leaves several open questions: are there individual predisposing factors to somatic modulation?
How strong is the association between the capability to somatically modulate tinnitus
and an underlying non-auditory disorder? Why patients that have concomitant hyperacusis
also have higher chances of tinnitus modulation?
Tinnitus can derive from age-related or hereditary hearing loss, acute or chronic acoustic trauma, ototoxic drugs including aminoglycosides, cisplatin and high doses of salicylate, other hearing disorders as well as from psychological
factors such as depression, anxiety, obsessive compulsive, mood, conversion, somatoform and other psychiatric disorders.
This type of tinnitus, called somatosensory tinnitus, could be a direct consequence of
a disorder of non-auditory musculoskeletal structures, a fundamental characteristic of tinnitus
as hypothesized by Levine or, most probably, an attribute of tinnitus favored by an underlying
somatic disorder that triggers existing neural connections between somatosensory and auditory
pathways.
Otolaryngol Open J. 2016; 2(4): 111-114. doi: 10.17140/OTLOJ-2-125