Defense Mechanism
The hearing structures of many species have defense mechanisms against injury. For example, the muscles of the middle ear (e.g. the tensor tympani muscle) in many mammals contract reflexively in reaction to loud sounds which may injure the hearing ability of the organism.
The idea that the acoustic reflex is a defense mechanism has been a topic for debate in recent years. Commonly cited counterarguments include:
- The types of sound that produce hearing loss (impact and continuous noise), were not present during the evolutionary history of mammals.
- The muscles that kink the ossicles are among the smallest in the body, and fatigue too quickly to be useful in the capacity of protecting against continuous noise.
- The reflex is too slow to protect against impact noises.
Read more about this topic: Hearing (sense)
Famous quotes containing the words defense and/or mechanism:
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—Sarah Patton Boyle, U.S. civil rights activist and author. The Desegregated Heart, part 3, ch. 2 (1962)