Throughout my studies as a mechanical engineering student I’ve been fascinated by the biological sensors that can convert mechanical signals into electrical ones via a process called mechanoelectrical transduction. One such sensor, the cochlear hair cell, plays a critical role in the hearing process. This hair cell has finger-like protrusions, called stereocilia, that extend from the cell into the fluid filled space of the inner ear. A single hair cell can possess dozens of these interconnected stereocilia, whose lengths and geometric arrangements can vary depending on the type of hair cell and its location within the cochlea. Collectively, these stereocilia are termed the hair bundle—a machine whose overall function is to transduce mechanical movement of the surrounding fluid and membranes into an electrochemical signal. These structures protrude from the apical surface of the hair cell, and deflect under the slightest of stimuli—making them effective sensors.
Our sense of sound depends on these mechanosensors and the surrounding machinery that keeps them alive and communicating with the auditory system. When dysfunction occurs, it can hinder our ability to interact with others, follow conversations, and leads to an overall reduction in quality of life. The majority of us will experience some form of hearing loss either due to age or traumatic noise. But many of us in the field of Hearing Research want that to change. In order for change to occur, we need more information about the way these cochlear mechanosensors work.
I am interested in the relationship between mechanical input and stimulation of the surrounding nerve fibers. I would like to understand why it is that some types of mechanical stimuli result in irreparable cell death and ultimately loss of hearing.