How Hearing Works

 
Anatomy of the Ear Philadelphia - Listen 2 Life Hearing Centers

  • Sound waves pass from the outer ear and move through the air toward the eardrum which vibrates with sound
  • From the eardrum, these sound vibrations pass to the bones in the middle ear then to the cochlea which causes fluid and tiny hair cells in the cochlea to move
  • Movement of the hair cells in the cochlea creates neural signals which are then harnessed by the auditory nerve which then transmits them to the brain for sound and speech interpretation

 

The ear is sort of like hearing aids: small pieces of advanced-level (organic) technology working together to produce sound. It does this by converting sound waves into sound by passing those waves through the outer ear, through to the middle and inner ear then on to the brain which interprets them.

Specifically, the ear consists of three main parts as you can see in the diagram above:

  • the outer ear which consists of the external ear and the ear canal, also referred to as the external acoustic meatus
  • the middle ear which consists of the ear drum and the three really small bones called the malleus, incus and stapes
  • the inner ear which consists of the cochlea, vestibular and cochlear nerves, also referred to as the auditory or acoustic nerve.

Sound travels through the air in waves, which when picked up result in a series of vibrations within the ear.

First, sound waves enter the outer ear and pass into the ear canal where the waves cause the eardrum to vibrate. The outer ear is shaped as it is purposely because it’s the optimum way to capture and direct sound waves through the ear canal to the eardrum.

Second, vibrations from the eardum are passed to the bones in the middle ear which also causes them to vibrate.

Third, vibrations (sound waves) from the malleus, incus, and stapes bones pass through to the cochlea in the inner ear where there are small hair cells and fluid that pass signals to the auditory (acoustic) nerve. The cochlea is a snail shell-shaped organ that contains a narrow end that picks up low frequencies and a wider end thag picks up higher frequencies. The auditory nerve, having received its signal from the cochlea, then signals the brain to understand and interpret it into sound.

If any bone, organ, or nerve are malfunctioning, hearing loss can result. Make sure to regularly schedule appointments with your hearing specialist if you detect any degree of hearing loss.