How does hearing work? From sound to auditory perception

The process of hearing is amazingly complex and fascinating. The finely tuned mechanisms of our hearing enable us to experience the world's variety of sounds. Our ear not only acts as a pure sound receiver, but also processes the incoming sound waves in an amazing way to enable us to perceive sounds precisely. In this article, you will learn more about the amazing capabilities of our auditory system.

The structure of the ear: three main parts for a unique function

The human ear consists of three main parts: the outer ear, the middle ear and the inner ear. These parts all play a crucial role in the process of hearing. But how exactly do they contribute to our ability to perceive the sounds and noises around us?

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The outer ear includes the pinna and the ear canal. The pinna catches the sound waves and directs them into the ear canal. The sound waves vibrate through the ear canal and hit the eardrum. These vibrations start the process of hearing. Just like a funnel that directs water into a bottle, the pinna directs sound deep into our ear.

The middle ear is home to three tiny bones: Hammer, anvil and stirrup - the ossicles. They are the smallest bone system in the human body and transmit sound waves from the air to the inner ear. This part also contains the tympanic cavity, an air-filled space that equalizes the pressure between the outer and middle ear. Here, a connection is created between the ear canal and the inner ear, a bridge that carries sound.

The cochlea is located in the inner ear. It is filled with fluid and contains thousands of hair cells. These hairs react to the smallest movements and convert them into electrical signals.

The path of sound:

From the auricle to the brain

The path of sound from the pinna to the brain can be thought of as a kind of relay race in which the baton - in this case sound - is passed from one team member to the next. At each step of the process, the sound changes and approaches its final form as a sound that our brain can recognize.

Step 1:

Recording the sounds through the outer ear

The sounds around us are sound waves that vibrate through the air. These waves hit the pinna, are bundled and directed into the ear canal.

Step 2:

Transmission to the middle ear

The sound waves strike the eardrum and cause it to vibrate. These vibrations are passed on to the ossicles, which amplify the vibrations and transmit them to the inner ear.

Step 3:

Conversion into electrical signals in the inner ear

The vibrations enter the cochlea and move the fluid inside. This movement is followed by the hairs of the hair sensory cells, resulting in electrical impulses.

Step 4:

Transmission of impulses to the brain

The electrical signals generated are picked up by the auditory nerve and transmitted to the auditory center in the brain. There they are interpreted as sounds and tones. The auditory nerve is like a messenger that carries the messages from the hair sensory cells to the brain.

Our hearing:

Frequencies and frequency ranges

The human ability to hear is impressive. We can perceive a wide range of frequencies. The normal frequency range that human hearing can cover is between 20 Hz and 20,000 Hz. However, it is important to know that our hearing can diminish over time, which can lead to hearing loss.

Modern solutions for hearing:

Hearing aids

If hearing loss occurs at some point, whether due to age or illness, there are various aids that can improve hearing. Hearing aids, for example, amplify sound waves so that they can be more easily received and processed by the ear.

However, hearing aids are usually designed to amplify all sounds, that is, both speech and ambient noise. This can be particularly problematic when watching television.

For this reason, faller audio has developed the OSKAR TV hearing amplifier for the hard of hearing. The portable loudspeaker amplifies dialog while watching TV and at the same time filters out disturbing background noise. This makes it a useful addition to a hearing aid.

Find out more about the OSKAR TV sound processor now