Video developed by Brandon Pletsch
The ear is comprised of much more than the cartilage appendage on either side of our heads. This visible portion of the ear (known as the auricle or pinna) is the beginning of only one component of the ear – the outer ear.
It gathers sound and routes it down the ear canal to the ear drum (tympanic membrane) where the outer ear ends. The larger the auricle the more effectively this is done. When we have trouble hearing, cupping our hand behind the ear gathers more sound waves.
The eardrum serves as the division between the outer ear and the middle ear. The middle ear is an air filled cavity which contains the auditory ossicles (ear bones). These bones, the smallest in the human body, are used in transmitting the sound waves from the vibrating eardrum to the cochlea.
The cochlea is the portion of the inner ear responsible for hearing. Within this fluid-filled, snail-shaped, bony capsule – only the size of a pea – the mechanical energy of the vibrating ear bones changes into an electromechanical energy by triggering the microscopic sensory “hair cells.” These hair cells, so named because of their appearance when viewed under a microscope, send neural impulses to the brain for interpretation. (As an aside, a separately functioning portion of the inner ear attached to the cochlea [the semi-circular canals] is responsible for the sensation of balance and acceleration.)