Mechanism of Hearing
The mechanism of the ear is shown in Fig.2.4. Sound waves from the air around are
collected by the pinna, travel down the meatus, and are conducted to the cochlea via
the three auditory ossicles (i.e. the malleus , the incus and the stapes which act as an
impedance device, matching the sound wave impedance in the air to that in the basilar
fluid) and the oval window. The vibrations conducted in the basilar fluid cause groups of
hair cells along the basilar membrane to move; this motion induces piezoelectric action
and the mechanical energy is converted to an electrical pulse which travels along the
auditory nerve to the brain [26, 27].
The inner ear is highly susceptible to injury and disease. Damage to the inner ear
may result in temporary or permanent hearing loss. The auditory nerve attached with
cochlea is mostly damaged due to noise.