What is the function of the tympanic membrane (TM)?

The tympanic membrane, commonly known as the eardrum, indeed serves a crucial function in dividing the outer ear from the middle ear. It acts as a boundary that separates these two regions, allowing for sound vibrations to be transmitted from the outer ear into the middle ear. When sound waves hit the tympanic membrane, it vibrates, and these vibrations are then passed on to the ossicles located in the middle ear. This process is essential for hearing, as it enables the conversion of sound waves into mechanical energy.

While the tympanic membrane has other important roles, such as providing some protection against foreign particles and balancing pressure between the outer and middle ears, its fundamental function is to separate these two anatomical areas. It does not primarily amplify sound, nor is its main role to serve as a barrier against infections. Instead, it functions more as a mediator in the hearing process, facilitating the transmission of sound vibrations.