To date, even the best advances in technology have been unable to reverse many types of hearing loss. But that may change, thanks to research in other animal species.
How hearing works
To understand how we may eventually be able to reverse hearing loss, you need to understand how the process works.
Hearing starts when a sound travels into the ear via soundwaves toward the eardrum. The eardrum vibrates and sends the vibrations to the middle ear, which boosts them and passes them on to the hair-like cells in the cochlea (inner ear), where they are transformed into electrical signals for the brain to read.
In humans, we develop hearing loss for a number of reasons, including loud noises, illnesses and age. Sometimes, hearing aids can help. Sometimes, they can’t.
Hearing in other species
In birds and fish, hearing can remain intact because the animals regenerate the sensory hair cells in the inner ear. Mammals don’t have this ability.
But a new study published in the European Journal of Neuroscience shows that researchers have been trying to recreate this process in mammals by using specific receptors, called ERBB2s, to activate the pathway.
In the first experiment, scientists tried to target the ERBB@ receptors in mice with a virus. In the second experiment, they tried to genetically modify the mice in order to activate the ERBB2 receptors. In the third experiment, they used two drugs to produce a response to ERBB2.
Although the researchers were able to regrow the sensory hair cells, they admit that hearing is a complex problem that will require more work.
“You have to regenerate sensory hair cells and these cells have to function properly and connect with the necessary network of neurons,” explains researcher Dr. Patricia White. “This research demonstrates a signaling pathway that can be activated by different methods and could represent a new approach to cochlear regeneration and, ultimately, restoration of hearing.”
