Sound Reception: Hearing begins when sound waves travel through the air and reach the outer ear. These waves are sent into the ear canal, where they contact the eardrum, causing it to vibrate.
Mechanical Amplification: The vibrations of the eardrum are then conveyed to three little bones in the middle ear called the ossicles: the malleus, incus, and stapes. These bones operate as a mechanical amplifier, enhancing the strength of the vibrations.
The amplified vibrations are subsequently transferred into the inner ear, notably the cochlea, a spiral-shaped, fluid-filled structure. As the fluid in the cochlea moves in reaction to the vibrations, it causes hundreds of hair cells to move. Know more about How Hearing Works?
Hair Cell Activation: These hair cells, which are positioned along the basilar membrane of the cochlea, serve an important role in transforming mechanical energy into electrical signals that the brain can understand. When the hair cells bend in response to fluid motion, neurotransmitters are released.
Auditory Nerve Transmission: Neurotransmitters stimulate auditory nerve fibres that are linked to hair cells. These nerve fibres join to form the auditory nerve, which transmits electrical signals to the brainstem and, ultimately, the brain.
Auditory Cortex Processing: The brainstem processes incoming auditory signals to determine pitch and loudness. The impulses are then transmitted to the auditory cortex, which is located in the temporal lobe and is responsible for complex processing.