An exciting discovery was just announced that helps illuminate the mechanics of hearing in the human body. While scientists have long understood that the auditory system converts sound waves in the air into electrical signals for the brain, the exact way the auditory system accomplished this wasn’t fully understood.
Researchers at the Harvard School of Medicine have isolated a single protein called TMC1 that is fundamentally responsible for how our auditory system sends signals of sound and orientation to the brain for processing our hearing and balance. Scientists have not just discovered that the protein is responsible for hearing, they also have mapped the mechanism that TMC1 makes use of to turn the sensation of sound wave vibration into electrical signals delivered to the brain.
How Hearing Works
Our auditory systems are a combination of our ears and our brain, connected to each other by the auditory nerve. Human ears are shaped approximately like a cone, a form that funnels sound waves towards our eardrum and inner ear. Within the inner ear tiny nerve cells called “hair cells” are sensitive to the vibration of sound waves. Different hair cells detect different frequencies of sound.
Exactly how the hair cells respond to sound is the key to transmitting incoming sounds to the brain as electrical information. The surface of a hair cell is covered with pores that can open in response to sound. The open pores become gateways for electrical signals, sending charged ions through to the auditory nerve creating an electrical signal for the brain to receive and process. The brain processes sound nearly instantaneously based on the electrical signals the hair cells send its way.
The newly elucidated protein, TMC1, acts as the gatekeeper of the pores on your hair cells. TMC1 is responsible for both the creation of the pores and the opening or closing response the pores have to sound. After observing membrane pores acting in other sensory roles in the body, and finding them present on the hair cells of the inner ear, scientists were fairly certain they were on the right track to clarifying how hearing works on a molecular level.
However, the journey to discovering TMC1’s role in the process wasn’t easy or simple. The protein was originally isolated and named over a decade ago, in 2002. Another Harvard discovery, TMC1 was known at the time to be essential to the process of hearing, but understanding the exact mechanics of what its pivotal job was were still unknown. The recent study looked first at the structure of the TMC1 protein and amino acids that may affect its performance in the ear. Then, researchers worked with mice observing changes to the hair cells of mice when their TMC1 proteins came into contact with different amino acids. After studying 17 amino acid reactions, 5 were found to have a dramatic impact on the pores, and demonstrated the pore action as a key component to hearing.
Protecting Your Hearing
By far, most hearing loss starts as damage to the inner ear. The hairs cells may be the gatekeepers of hearing but they are also incredibly fragile and irreplaceable mechanisms. When a hair cell becomes damaged it is unable to repair itself. Instead, it falls out of commission, and ceases to send signals to the brain about the incoming sound waves it receives.
We only get 16,000 hair cells in each ear and when they’re gone, our ability to hear is gone with them. Loud noise is the most common culprit for damaging our hearing. Sounds at 85 decibels and above can cause permanent hearing loss if you are overexposed to them. Age also plays a factor in several ways. As we get older, more and more of our hearing is lost, which eventually adds up to significant hearing loss. Our hair cells also become more brittle and delicate as we age, making it much easier to harm our hearing the older we are.
Visit Us at Gulf Gate Hearing Aid Center
While hearing loss is permanent, it can be treated with hearing aids. When you are experiencing hearing issues, that’s where Gulf Gate Hearing Aid Center can help. We help people like you hear better, richer sound through personalized hearing analysis and comprehensive selection of hearing products. Don’t wait if you have a hearing issue – call us today!