The inability to hear properly can cause widespread difficulties for older adults. Not only is it a frustrating condition that can lead to social isolation, depression, and anxiety, hearing loss can also cause day-to-day activities to take a dangerous turn. An otherwise healthy senior who suffers from hearing loss could face the reality of needing a great deal of outside help, which is not always possible. Hearing aids have come a long way toward alleviating some of the larger issues of declining hearing. The development of cochlear implants was a dream come true for people suffering from hearing loss—within the last few years, social media has exploded with heartwarming videos of people who’d spent their lives in silence and were suddenly thrust into the hearing world via implants. Now science has taken it one step further. A recent study demonstrates that it may be possible to regrow the sensory cells in the inner ear in patients with age or noise-related hearing loss.
The study, published in the European Journal of Neuroscience, demonstrates that scientists were able to successfully regrow the sensory hair cells in the cochlea. Those are the cells responsible for converting sound vibrations into the signals needed for us to hear them, and they can often become damaged as we age. Unlike other areas of the body, once those cells are damaged, the ability to fully hear is gone for good. One in three people in the United States between the ages of 65 and 74 has some level of hearing loss, and almost half of people over the age of 75 suffer from an inability to hear properly, making this a far more widespread issue than many people realize.
Age-related hearing loss can be a side effect of things such as high blood pressure and diabetes—even medication—as well as the result of prolonged exposure to excessive amounts of noise. In most older adults, hearing loss is a combination of the two. While being mindful of excessive noise is a simple way to protect your hearing, unlike many conditions of advanced age, there are not many things that can be done to prevent age-related hearing loss as we grow older.
Researchers took a look outside to determine why it was that some animals, birds and amphibians were able to successfully regrow sensory hair cells, something humans do not have the ability to do. It seems to be a quirk of evolution, and scientists are now examining a way to alter that element of human hearing to allow for regeneration of hair cells and a connection with nerve cells to allow for better hearing. The focus of their research was on a receptor in cochlear support cells called ERBB2. By manipulating this receptor, they were able to successfully coax cochlear support cells into growing and switching adjacent cells to turn ‘on’ essentially creating new sensory hair cells.
The question now is whether these results will be successfully replicated in human subjects, but the progress is encouraging. While cochlear implants may have sounded like something out of science fiction fifty years ago, in another fifty years, humans may have no need for them after all.