Auditory Disability: General Characteristics, Types and Causes

The hearing impairment is any type of condition that produces a decrease in the capacity of perception of sound, which in turn generates difficulty for verbal communication. Hearing impairment is not a disease in itself.

East type of disability rather it is the consequence of different medical conditions that generate permanent or transitory damage to the different structures of the ear. People with hearing disabilities can have a totally normal life.

Within this normal life includes professional development, homework, sports and any other type of activity of daily life, even if to achieve this goal is necessary in many cases that have special assistance.

Characteristics of hearing impairment

-It occurs when part or all of the ability to listen is lost. Other terms that are used to refer to hearing impairment are deafness or hearing problems.

-The auditory disabilities are classified in terms of the severity and type of hearing impairment. Gravity is categorized based on the minimum sound that can be heard with the best ear. The higher the decibel (dB), the stronger the sound.

-A hearing loss greater than 90 decibels is generally considered deafness. A hearing loss of less than 90 decibels is classified as a hearing disability.

- There are communication and educational obstacles related to hearing deficiencies arise around communication. A student with a hearing disability may experience difficulties in: grammar, spelling and vocabulary, take notes, participate in discussions, watch videos or present oral reports.

-It is important that the parents and teachers of a child with a hearing impairment do not underestimate their intelligence. Most children with this disability acquire and develop language more slowly and because of this it can be incorrectly assumed that intelligence is low.

-Although the Sense of hearing has been affected, the person can lead a normal life.

Types

Classifying the auditory disability is extremely complex, since it is difficult to encompass all the edges of such a complex problem in a single classification. Thus, we can distinguish several types of hearing impairment according to their characteristics, not necessarily being mutually exclusive.

According to the moment of appearance

Congenital

The person is born with the disability, either by malformation of the structures that make up the ear or by an abnormal functioning in the cellular and even molecular sphere.

At this point it is important to note that not all congenital deafness is detected early; in fact, they are divided into two large groups: the hearing disability that appears between birth and 3 years, and that which occurs after 3 years of life.

Acquired

The disability develops throughout life due to multiple factors that can be genetic, traumatic, toxic (drugs and drugs) and degenerative (aging).

In some cases of acquired hearing disability, two different factors may be added throughout life, which are enhanced by increasing the severity of the situation.

For example, a person had an acoustic trauma during youth generating auditory disability, although retaining a certain degree of hearing.

Later in his life he receives prolonged treatment with an ototoxic drug (as are certain antibiotics of the aminoglycoside group), which can cause more damage to an already diseased ear; in this case both causes are added.

According to the severity

Hearing impairment is understood as any degree of hearing loss that interferes with sound perception processes at a level that requires the use of special aids to achieve adequate hearing (if this is possible).

In this sense, according to its severity the auditory disability can be classified as:

Cofosis

It is also known as deep deafness. The person is unable to perceive any type of sound.

Deafness

Sounds above 75 dB are needed to achieve hearing. Technically the person is deaf but it is not a profound deafness (as in the case of the cofosis), since with sounds amplified by devices designed for this purpose, you can achieve a relatively acceptable hearing.

Hearing loss

You can perceive sounds below 75 dB but not in the full range of normal hearing.

To be able to diagnose any of these conditions, an audiometry must be performed, which will yield one of the following results:

- Normal hearing, which means that you can perceive sounds in the range of 20 dB or less.

- Mild auditory loss, in which the minimum range of detectable sound is between 20 and 40 dB.

- Average hearing loss, which implies that it can detect sounds as of 40-70 dB (hearing loss).

- Severe hearing loss, with which he is only able to detect sounds between 70 and 90 dB (deafness).

- Deep hearing loss, with which, at best, manages to detect sounds above 90 dB (deep deafness) or does not detect sounds at all (cofosis).

It is important to emphasize that the different conditions that produce a decrease in the perception of sound can be unilateral or bilateral.

In cases in which the problem is unilateral, the healthy ear can compensate the situation and allow the person to have a relatively normal life without the need for hearing aids, although sometimes it will have problems to evaluate where a sound originated.

On the other hand, when the problem is bilateral, a disability is already considered that requires special aids and techniques to allow the person to function normally in their social environment.

According to the forecast

The auditory disability can be permanent or transitory. In the first case the hearing does not recover and may even get worse over the years until reaching the coosis.

In the second case, the auditory disability is transitory and eventually the affected person can recover a normal hearing, or reach the range of mild-moderate hearing loss without this implying a disability.

According to the site of the injury

They are divided into two large groups:

Driving deafness

When the problem is in the outer ear or the middle ear. They are usually the ones with the best prognosis.

Sensorineural deafness

In these cases the lesion is in the inner ear, in the nerves that carry the auditory impulse and even in the auditory cortex itself, where the brain interprets the sounds.

Causes of hearing impairment

Hearing impairment has many causes, some more common than others. Next, mention will be made of the most common in both children and adults.

Causes in children

Although infrequent, there are congenital causes of deafness in children. In general, the hearing deficit is associated with other features of a particular syndromic complex, with more than 400 syndromes in which hearing loss is present.

Among these we can mention the Waardenburg syndrome , characterized by partial albinism and deafness; he Usher syndrome , where hypoacusis and visual defects are associated; and Alport syndrome, characterized by deafness and renal dysfunction.

In these, as well as in all cases of congenital deafness of genetic origin, a particular gene has been identified, which can be inherited to the next generation.

In most cases of congenital deafness the problem is at the height of the cochlea; that is, in the receivers located in the inner ear. However, there are certain congenital conditions - such as hypoplasia of the external auditory canal or malformations of the auricle. - that are related to this type of disability.

In these cases the surgical reconstruction of the structures with problems can lead to the recovery of the auditory potential.

Perinatal causes

More frequent than deafness of genetic origin is deafness due to perinatal factors, among which are prematurity, low birth weight, infections of the mother such as rubella or toxoplasmosis, as well as the treatment of the mother during pregnancy with ototoxic drugs.

All these predispositions can cause hearing problems in the newborn. These problems can manifest from the moment of birth or later in life, even beyond 3 years.

During early childhood the baby is very vulnerable to external elements that can injure the ear. Infections such as viral meningitis, mumps, and even measles can leave behind a certain degree of hearing impairment.

On the other hand, repeated otitis, trauma and the use of ototoxic drugs during the first years of life can cause deafness.

A frequent cause of diminished hearing (but not disability unless the cause is corrected) is the introduction of foreign bodies into the external auditory canal, as well as the formation of earwax plugs. In these cases the decrease in hearing ability is easily corrected by eliminating the cause.

Causes in adults

In young adults the most frequent causes of hearing impairment are the use of ototoxic drugs or drugs, and acoustic trauma from exposure to sounds above 100 dB, such as: explosions, detonation of firearms, equipment noise industrial, music at high volume, among others.

In these cases, the hearing loss may be transient or permanent, depending on the intensity of the sound, the exposure time and the severity of the damage.

On the other hand, certain tumors such as acoustic nerve neuroma can cause deafness.

In older adults there may be conditions such as earwax, which causes a reversible conduction deafness when the hearing is recovered when the earplug is removed.

Aging

On the other hand, as you get older, a condition known as otosclerosis may occur, in which the joints of the middle ear grooves become stiffer, resulting in poorer sound conduction. In the end, this generates deafness of progressive and irreversible driving.

Something similar happens with the middle ear receptors, which degenerate and become less effective, conditioning the natural hearing loss of the elderly.

Treatment of hearing impairments

The treatment of the hearing disability must be individualized according to each case. The priority is to correct the cause; if not possible, they will be used from microamplifiers to cochlear implants to ensure that the patient can recover their hearing.

In the case of childhood deafness, early diagnosis is very important, because the earlier the problem is identified, the better the prognosis.

In the most severe and irreversible cases, the treatment focuses on providing the person with tools that allow him to act in his daily life, such as sign language and other strategies that will allow him to have a happy and functional life.

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