Anatomically, the human ear is composed of three parts – outer, middle and inner ear. Each of these parts has a specific function in the process of hearing.


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The pinna, auditory canal and eardrum make the outer, or external ear. This part of the ear receives sounds and transmits them to the eardrum through the auditory canal. In addition to the transferring function, the ear canal also serves as a resonator and slightly enhances the sounds. In this way, each sound gets to keep its intensity in the course of further transmission from the middle to the inner ear.

The middle ear begins with the eardrum. Next to it we have the auditory ossicles, which are the smallest bones in the human body, known as hammer, anvil and stirrup. These hinged ossicles, transmit the sounds from the eardrum to the inner ear. Thanks to their hinge connection and exceptional mobility, they enable a good quality transfer of the acoustic signals from the outer to the inner ear.

The inner ear is the receptive part of the ear, containing the organ of Corti. This is the most important part of the human hearing organ, converting the sounds from the environment into nerve impulses and sending them further through the cochlea, or auditory nerve, to the brain.

How Do We Hear?

The ear registers a sound, by receiving it through the outer ear. Then, the sound waves are transmitted through the middle ear to the organ of Corti in the inner ear, where they are converted into nerve signals. This is when the cochlear nerve actives and send the signals to the central structures of the brain, where they are “deciphered” and created into something that makes sense and we understand.

The range of human hearing includes frequencies from 20 to 20,000 Hz. Of course, these numbers differ from person to person and are often influenced by various factors, such as age and ear damage. That’s why, as we grow older, our ability to hear reduces.

Hearing Impairment

Hearing impairment is a reduced sensitivity of the auditory system. This is one of the most common health problems, which can affect all age groups. Physiologically induced hearing loss, due to age, is still the most common cause of this impairment. The reason behind it can be located in any of the hearing organs.

If the damage occurs in the outer ear, the ear canal or middle ear, we talk about conductive hearing loss. If the damage is in the inner ear, the cochlea, or in the cochlear nerve, it’s a sensorineural hearing loss (SNHL).

Conductive hearing loss is usually temporary and it can be corrected with medications or a surgery. When it comes to SNHL, it cannot be corrected. This is the most common type of permanent damage of the auditory perception.

Test And Diagnosis

The most widespread method of determining the damage of the hearing sense is the pure tone audiometry. This is a completely painless method of measuring the hearing thresholds and the frequency at which the hearing is damaged.

The following video can help you test how high are the frequencies that you can hear.

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