The stapedius muscle is the smallest striped muscle in the human body that has the ability to contract, claims a 2007 study in the Polish Journal of Otorhinolaryngology. The stapedius muscle automatically contracts as a result of aural stimulation. It is located in the middle ear, and it only measures about 1 millimeter, or 1/26 of an inch, in size.
The stapedius muscle is located in the ear and blocks excessively loud noises, according to Timothy Hain, MD. The doctor goes on to say that an overactive stapedius muscle can result in hearing problems, such as tinnitus. Also, according to Dr. Hain, one of the main functions of the stapedius muscle is to muffle the noise caused by chewing. Without the stapedius muscle and its automatic reflex, chewing would be unbearably loud for humans, he claims.