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Special Senses
Published in Pritam S. Sahota, James A. Popp, Jerry F. Hardisty, Chirukandath Gopinath, Page R. Bouchard, Toxicologic Pathology, 2018
Kenneth A. Schafer, Oliver C. Turner, Richard A. Altschuler
The middle ear contains a chain of three small bones called the ossicles. These are most often termed the malleus, incus, and stapes but also termed the hammer, anvil, and stirrup respectively. The malleus (hammer) is attached to the tympanic membrane and articulates with the incus (anvil) (Figure 23.5a). The incus articulates with the stapes (stirrup) and the footplate of the stapes is attached to the membranous oval window of the cochlea. There are two muscles associated with ossicles; the tensor tympani muscle (innervated by the trigeminal nerve) is attached to the malleus and the stapedius muscle (innervated by the facial nerve) is attached to the stapes. Contraction of these muscles is associated with a reflex induced by loud sounds and contraction of the muscles restricts movement of the ossicles and reduces transmission of sound.
Noise-Induced Hearing Loss and Related Conditions
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
Andrew McCombe, David M. Baguley
The problem of acoustic shock is very different and is thought to be more of an acute stress reaction. It is found typically in call-centre workers who are under some pressure to process high volumes of calls in a defined time period. The sound comes through their headsets and may be the result of a technical malfunction, or a malicious act by the individual on the other end of the phone line. The sound is unexpected and is perceived as both loud and unpleasant by the affected individual, although when measured it may be less than classically damaging sound levels of 85 dB(A) or above. Objective hearing loss is rarely a feature but multiple symptoms and high levels of psychological distress are often described. Common symptoms are summarized in Table 57.2. Theories exist that the problem represents a combination of an excessive ‘startle’ response, and/or a form of post-traumatic stress disorder.54 In addition, there is a view that myoclonic activity of the tensor tympani muscle is involved.50 The degree of psychological distress is often enough to force the individual to leave the job where the exposure occurred.
Anatomy
Published in Stanley A. Gelfand, Hearing, 2017
Returning to the medial wall, we see that the oval window is located posterosuperiorly to the promontory, while the round window is posteroinferior to the latter. Superior to the oval window lies the facial canal prominence with the cochleariform process on its anterior aspect. The tendon of the tensor tympani muscle bends around the cochleariform process to proceed laterally to the malleus.
First emerging objective experimental evidence of hearing impairment following subarachnoid haemorrhage; Felix culpa, phonophobia, and elucidation of the role of trigeminal ganglion
Published in International Journal of Neuroscience, 2019
Metin Celiker, Ayhan Kanat, Mehmet Dumlu Aydin, Dogukan Ozdemir, Nazan Aydin, Coskun Yolas, Muhammed Calik, Halil Olgun Peker
In our opinion, the vasodilation of the TGG artery can be diminished by a lower neuronal density in the TGG, and this vasospasm cause to lower phonophobia scores in SAH. We showed the degeneration of TGG as a cause of hypoacusia following SAH, The nerve of this ganglion is trigeminal nerve is the principal sensory nerve to the tympanic membrane. The vibration of the eardrum is thought to stimulate the ipsilateral trigeminal nerve, leading to contraction of the tensor tympani muscle [19]. Tensor tympani muscle augments the strain of eardrum and increases in sound severity and facilitate hearing. There is evidence that the tensor tympani muscle and the stapedius muscle, modulate acoustic input by influencing the ossicular chain in rabbits [20]. The stapedius muscle is innervated by the facial nerve. Paralysis of stapedius muscle innervating branch of facial nerve cause hyperacusia [21]. Thus, the attenuation effect of the acoustic stapedius reflex protects the inner ear from acoustic damage. In this study, we first-time demonstrated the protective effect of the tensor tympani following SAH.
Dizziness handicap inventory and vestibular activities of living scale in patients with temporomandibular dysfunction
Published in Hearing, Balance and Communication, 2018
Bianca S. Zeigelboim, Adriana B. Lacerda, Vinicius R. Fonseca, Paulo B. Liberalesso, Jair M. Marques, Jéssica S. Malisky, José Stechman Neto
Some authors [6,9,19,24] have reported that hyperactivity of the masticatory muscles caused by malfunctions in the stomatognathic system could be reflected in the tensor tympani muscles and tensor palati, as well as in otomandibular ligaments, being cited in the literature as being responsible for the emergence of auditory symptoms, particularly tinnitus. According to Ramírez et al. [25], abnormal activity of the tensor tympani muscle is associated with auditory and vestibular symptoms such as ear fullness, tinnitus, vertigo, hypo/hyperacusis and earache.