Reissner’s Membrane (RM), also known as the Basilar Membrane (BM), is a membrane situated in the mammalian cochlea between the inner and outer hair cells. It is named after German physicist Ernst Reissner, who first described it in 1851. The primary role of RM is to facilitate the conversion of acoustic waves into electrical signals by transducing sound energy into mechanical energy. The RM is composed of a number of layers of specialized cells, including the outer hair cells, the inner hair cells, and the supporting cells. These cells are arranged in a precise manner to ensure that sound waves are accurately transduced into electrical signals.
The primary function of the RM is to convert sound waves into electrical signals. This is achieved through a series of steps involving the active movement of the outer hair cells. When an acoustic wave enters the cochlea, the RM is subjected to vibration. This vibration causes the outer hair cells to move in a specific direction, which in turn causes the cell membranes to change shape. This change in shape results in a change in the electrical potential across the membrane, thus generating an electrical signal that can be processed by the auditory system.
The RM also plays an important role in the perception of loudness. Studies have shown that the RM is capable of accurately detecting sound intensity even at very low levels. This allows the auditory system to distinguish between sounds that are very loud and those that are very soft, enabling the brain to interpret the nature of the sound.
In addition to transducing sound energy into electrical signals, the RM also plays an important role in the maintenance of the cochlear environment. The RM is responsible for maintaining the balance of fluid pressure in the cochlea, allowing the hair cells to receive a constant supply of nutrients and oxygen. The RM also helps to protect the delicate hair cells from damage caused by loud noises.
Overall, Reissner’s Membrane is a critical component of the mammalian auditory system. Its ability to accurately transduce sound energy into electrical signals, as well as its role in maintaining the cochlear environment, are essential for normal hearing.
References
Fay, R. R., & Popper, A. N. (2000). The mammalian cochlea. Springer.
Hudspeth, A. J., & Lewis, R. S. (1999). The active cochlea. Nature, 399(6734), 39–44.
Plontke, S. K., & Kössl, M. (2005). Basilar membrane mechanics and cochlear amplifier. Hearing research, 203(1-2), 17–31.
Pujol, R., & Lopez-Poveda, E. A. (2003). Active control of basilar membrane vibration by the outer hair cells: its contribution to the frequency selectivity of the cochlea. Hearing research, 183(1-2), 11–25.