How We Hear
Functioning of the ear
The ear is a key organ enabling communication with the world around us and is divided into three parts:
- The outer ear comprises the auricle (the visible outer part), the eardrum and the ear canal. The outer ear captures the sound waves and sends them into the auditory canal, where they cause the eardrum to vibrate.
- The middle ear consists of three small auditory ossicles that connect the eardrum to the inner ear. The vibrations in the eardrum cause the three auditory ossicles in the middle ear to vibrate.
- The inner ear includes the auditory spiral or the so-called cochlea. This converts the sound to nerve impulses that it transmits to the brain. The vibrations from the middle ear stimulate thousands of hair cells in the cochlea. The resulting movements are converted into electrical impulses, which the brain finally perceives as sounds.
Hearing loss is a widespread phenomenon
Hearing impairment is more widespread than you may think. Approximately 15-20% of the population in the industrialised world suffer from it. Age-related hearing loss occurs when the hair cells in the inner ear lose their flexibility over the course of a person’s life. Although the outer ear continues to capture sound waves as before and to transmit them via the outer and middle ear, the inner ear is unable to pick up the sound vibrations and to transmit them to the brain.
The natural ageing process is, therefore, the most common cause of hearing impairment, accordingly, a perfectly normal phenomenon with increasing age.