Researchers at Yale University have made an exciting discovery about how our ears perceive sound. They aimed to understand how the inner ear detects faint sounds without becoming overwhelmed by noise. Their findings could reveal how we hear extremely low frequencies better.
Physicist Benjamin Machta explained their goal: “We wanted to find out how the ear fine-tunes itself to hear soft sounds while avoiding instability.” In their research, they uncovered new low-frequency mechanical modes in the cochlea, the snail-shaped organ that plays a key role in our hearing.
The cochlea’s tiny hair cells react to vibrations, sending signals to the brain that allow us to hear. These vibrations can fade as they travel along the cochlea, dulling tones and reducing volume. However, it has long been known that specific areas of the cochlea can amplify these vibrations with precise timing, enhancing our ability to hear certain tones.
Interestingly, the research suggests that the ear can also broadly tune into surface waves, balancing and canceling out unwanted noise while preventing confusion from false sounds. This capability helps maintain clarity in what we hear.
The team discovered that large sections of the basilar membrane in the cochlea can work together for lower frequency sounds. This teamwork aids the cochlea in managing incoming vibrations, protecting our ears from being overwhelmed by louder sounds.
These insights deepen our understanding of the cochlea and how our hearing functions, potentially shedding light on hearing problems as well. Isabella Graf, a theoretical biophysicist involved in the study, emphasized that these findings could help us better grasp low-frequency hearing, a topic still under study.
Low-frequency hearing ranges from 20 to 1000 Hz, and the behavior of the hair cells they observed appears vital for detecting quieter sounds. The researchers are excited to explore how these newly found modes affect hearing in their future work.
Their research has been published in PRX Life.
