The function of the tensor tympani muscle: a comprehensive review of the literature

Abstract

The tensor tympani muscle is structurally important in the middle ear, specifically through its involvement in the impedance of sound in response to intense auditory and non-auditory stimuli. Despite numerous studies, its true function has been debated for many years; questions still remain about its role in auditory and non-auditory reflexes and in sound damping. Some studies suggest that the tensor tympani muscle contracts as a result of non-auditory stimulation such as facial or head movements; others suggest that it contracts due to input from the cochlear nucleus, therefore by way of auditory stimulation. Whatever the cause, contraction of the tensor tympani muscle results in low frequency mixed hearing loss, either to protect the inner ear from loud sounds or to desensitize the ear to self-generated sounds. A review of these studies indicated that the tensor tympani muscle has a wide range of functions, yet the mechanisms of some of them have not been clearly demonstrated. One major question is whether the tensor tympani muscle contributes to sound damping; and if it does, what specific role it serves. The primary purpose of this review article is to explore the functions of the tensor tympani muscle in light of recent research advances.

Masseter Vestibular evoked myogenic potentials: A new tool to assess the vestibulomasseteric reflex pathway

“…The similarity between the two pathways (The acoustic-masseteric reflex pathway and the tensor tympani reflex pathway) is both get stimulated as a startle reflex when there is a loud sound. The tensor tympani reflex pathway also gets stimulated to non-auditory stimuli and self-generated sounds such as chewing and swallowing ( Mukerji et al, 2010 ; Edmonson et al, 2022 ). Fig.…”

Unique fiber phenotype composition and metabolic properties of the stapedius and tensor tympani muscles in the human middle ear

“…Even though contractions of the tensor tympani muscle have been audiometrically shown to result in low-frequency mixed hearing loss (Wickens et al, 2017), there is evidence that the tensor tympani in humans is not activated by loud sounds from the environment and has non-acoustic functions (Salomon & Starr, 1963). Several reports agree that the muscle is activated when exposed to self-generated auditory stimuli such as swallowing, speaking, or chewing and nonauditory stimuli in the anticipation of loud sounds (Edmonson et al, 2022).…”

Bibliometric Analysis of Publications on Stapedius Muscle

“…It contracts in reflex synchronization with the tensor tympani muscle. Its function is to prevent excessive movement of the stapes and reduce the amplitude of sound [3,4]. The stapedius muscle is innervated by the facial nerve, and paralysis of the stapedius muscle may cause hyperacusis, a condition in which patients perceive normal sounds as abnormally loud [5,6].…”