title: Evaluation of tensor tympani muscle dominance in the biphasic acoustic reflex.
abstract: The Acoustic reflex frequently causes a biphasic change in impedance at onset. Understanding the cause of the biphasic response is important for establishing a physiological basis for the clinical measurement of reflex latency. The decrease in impedance at onset may be due to uncoupling of impedance contributed by the cochlea. Subsequent increases in impedance predominantly reflect stapedius muscle activity. The clinical implications of this physiologic model are discussed.
mesh_terms: D000158:Acoustic Impedance Tests; D000818:Animals; D003051:Cochlea / Q000502:physiology; D004424:Ear Canal / Q000502:physiology; D005154:Facial Nerve / Q000502:physiology; D008252:Macaca fascicularis; D008253:Macaca mulatta; D008297:Male; D011930:Reaction Time; D012022:Reflex, Acoustic; D013198:Stapedius / Q000502:physiology; D013719:Tensor Tympani / Q000502:physiology*; D014432:Tympanic Membrane / Q000502:physiology*