The reason hearing loss is so difficult to cure is because of the way that your ears work.
Sound travels into your ear canal as vibrations in the air.
Those vibrations hit your eardrum, that’s like a sheet of skin, and it’s converted into movements in a series of tiny bones.
These bones amplify the vibrations and send them into the cochlea, which is a hollow, spiral bone filled with fluid.
So, to put it simply, your ear takes vibrations in the air and converts them into waves of fluid inside your cochlea.
Then the final stage is that the walls of the cochlea are covered in hair cells with tiny filaments called stereocilia.
As these stereocilia move around in the waves of fluid, that is converted into electrical signals that are sent to your brain to be processed as sound information.