Don’t worry, your alarm clock probably isn’t causing hearing loss. Well, at least not during the day! Let me explain. You probably know that your sleep patterns, hormone levels, body temperature, and immune system are affected by circadian rhythms, which are controlled by biological clocks. Circadian rhythms have also been linked to obesity, diabetes, heart disease, metabolism, and depression- and new research shows a potential link to hearing loss.
Researchers at the Karolinsksa Institutet in Stockholm have discovered that there is a biological clock in the ear, controlled by genes that regulate circadian rhythms. Through research in mice, they found that higher noise levels during the night resulted in permanent hearing damage, but the same noise levels during the day didn’t affect their hearing.
There is a growth hormone (called BDNF) that protects auditory nerve cells. These levels fluctuate through the day, regulated by your ‘ear clock.’ BDNF levels were lower at night, so the mice were more prone to hearing damage. But by stimulating BDNF levels at night, researchers were able to protect hearing during noise exposure!
This is an important discovery. Many people work in professions that expose them to higher noise levels at night, and understanding the mechanisms behind protecting hearing could help researchers develop new treatments for hearing loss. Read more about it here: