Cochlea a protein motor called prestin on their outer membranes; it generates additional movement that couples back to the fluid–membrane wave. This "active amplifier" is essential in the ear's ability to amplify weak sounds. The active amplifier also leads to the phenomenon of soundwave vibrations being emitted from the cochlea back into the ear canal through the middle ear (otoacoustic emissions). Otoacoustic emissions are due to a wave exiting the cochlea via the oval window, and propagating back through the middle ear to the eardrum, and out the ear canal, where it can be picked up by a microphone. Otoacoustic emissions
The Body (1970 film) The Body (1970 film) The Body is a 1970 UK scientific documentary film directed and produced by Roy Battersby. In the film, external and internal cameras are used to showcase the human body. The film's narrators, Frank Finlay and Vanessa Redgrave, provide commentary that combines the knowledge of human biologists and anatomical experts. The film's soundtrack, "Music from the Body", was composed by Ron Geesin and Roger Waters, and includes songs that were made using the human body as a medium. Waters is also the narrator of one scene. In August 1971 Nat Cohen, whose company distributed the film, said