How We Hear

Hearing is the access to the world surrounding us and key for communication and forming human connections.

Hearing starts with sound entering the ear canal where it leads to vibrations of the eardrum. These sound vibrations are transmitted to the inner ear via the ossicles, the three small bones of the middle ear.

The inner ear contains the cochlea including approximately 15,000 sensory cells, so-called hair cells. The inner hair cells convert sound vibrations to electrical signals that are transmitted via the auditory nerve to the brain, while outer hair cells amplify the signals up to 10,000-fold.
Hair cells of the human ear encode tone frequencies in a range of 20 to 20,000 Hz. Only if they are functional, sound can be decoded by the brain as music or speech.

Several factors, such as illness or aging can damage hair cells as well as their connections to the auditory nerve. Sudden hearing loss is a medical emergency which requires immediate attention by a doctor.