Sensorineural hearing loss is a type of hearing loss caused by damage to the auditory nerve and inner ear structures. This damage can be congenital or acquired. While individuals with sensorineural hearing loss may sometimes hear a little, the sound typically reaches them muffled and distorted.
Sensorineural hearing loss can affect one ear or both, and symptoms can appear gradually or suddenly. When it occurs suddenly, it is called sudden sensorineural hearing loss. Unlike the latter, the symptoms of classic sensorineural hearing loss often develop slowly and may go unnoticed until a hearing test is performed. As sensorineural hearing loss progresses, some of these symptoms become evident. The most common symptoms of sensorineural hearing loss are:
Difficulty understanding female and children's voices.
Difficulty understanding spoken speech. You may hear what is being said, but you cannot understand it. This means that the ear is receiving the sound, but the process that translates this sound into understandable information is not working correctly.
Vertigo. The organ responsible for balance is also located in the inner ear. Any damage to the inner ear can disrupt your balance and cause dizziness, vertigo, or loss of balance.
Muffled sounds. Your ear picks up external sounds, but they are muffled and not clear enough to be understood; this can lead you to constantly ask your interlocutor to repeat themselves.
Difficulty hearing when there is background noise.
Difficulty hearing high-pitched sounds. Low-pitched sounds are easier to perceive with sensorineural hearing loss.
Tinnitus. This is the perception of a sound in the ear when no external sound source exists. In individuals with sensorineural hearing loss, tinnitus most often manifests as a continuous ringing.
Sensorineural hearing loss is divided into three main categories based on the extent of the damage. The degrees of sensorineural hearing loss are:
Mild sensorineural hearing loss: This is the subject of this article. Sensorineural hearing loss is considered mild when it is between 26 and 40 decibels.
Moderate sensorineural hearing loss: Any hearing loss between 41 and 55 decibels is classified as moderate sensorineural hearing loss.
Severe sensorineural hearing loss: This type of hearing loss begins at 71 decibels and above.
What is mild sensorineural hearing loss?
Mild sensorineural hearing loss is the most common, but also the most underdiagnosed, degree of hearing loss. The fact that it is called "mild" does not mean it is without consequences for those affected. People with mild hearing loss cannot hear sounds louder than 40 decibels and softer than 25 decibels. Children with mild sensorineural hearing loss cannot hear sounds softer than 15 decibels. Sounds within this decibel range include shuffling footsteps, whispered speech, dripping water, birdsong, quiet conversations, and rustling leaves. People with mild sensorineural hearing loss can communicate without too much difficulty in a quiet, one-on-one setting. However, in a noisy environment, they may be unable to follow a conversation or hear the most discreet ambient sounds. They also have difficulty understanding speech at a distance, in large groups, or on the phone. Due to the very subtle nature of mild sensorineural hearing loss in its early stages, most people do not quickly realize they have a hearing problem. They often attribute their difficulty hearing to background noise or the low volume of their interlocutor's voice. People with mild sensorineural hearing loss also hear when someone speaks loudly, but they sometimes feel like their ears are blocked or that their interlocutor is mumbling. Difficulty hearing and understanding speech occurs when multiple sound signals compete, for example, noise and speech at the same time. Hearing women's and children's voices as well as very high-pitched sounds, like the most piercing alarms, can also be challenging.
The effects of mild sensorineural hearing loss on communication
Although it is described as "mild," mild sensorineural hearing loss nonetheless poses real communication difficulties with others. These individuals generally have no trouble understanding speech when their interlocutor is very close to them or when the environment is quiet. But since these conditions are not within their control, they experience communication difficulties at certain times. In other words, if you suffer from mild sensorineural hearing loss, you will not always be able to silence your surroundings when someone speaks to you, especially in public places. Nor will you always be able to bring the speaker closer to you, especially if you are not the only recipient of their message. This inability to control your interlocutor and your environment makes mild sensorineural hearing loss all the more noticeable. Due to the variable circumstances in which people with mild sensorineural hearing loss are able to hear, some are criticized by those around them for only hearing when they choose to. It is often implied that the hearing-impaired person is feigning deafness or pretending not to understand. In addition to the inability to hear speech at a distance, people with mild sensorineural hearing loss have difficulty understanding words containing certain consonants. Consonantal sounds like "S," "K," "F," "Ch," and "Th" can be difficult to grasp. These consonantal sounds are indeed softer than other more distinct consonants. Thus, even if speech is loud enough to be heard, it may remain unintelligible. In most cases, the hearing-impaired person hears the word, but struggles to clearly distinguish it from similar words. For example, the word "chemise" (shirt) may be heard as "cerise" (cherry), and "poisson" (fish) as "poison" (poison). Because of this difficulty hearing and understanding certain words, people with sensorineural hearing loss often listen more attentively and put in more effort to understand what is being said. This requires a lot of energy and can lead to fatigue. This fatigue sometimes prevents them from sustaining a conversation for a long period. Children with mild sensorineural hearing loss often experience more difficulties than adults. This is because children need a higher level of speech than adults in the presence of background noise. They also lack an extensive vocabulary and the necessary experience to compensate. Depending on the noise level at school, children with mild sensorineural hearing loss may miss about twenty to forty percent of speech and nearly half of classroom discussions. This can lead to academic difficulties. All problems related to mild sensorineural hearing loss can impair the communication of the hearing-impaired person. Over time, these communication difficulties can lead to problems in social interactions, interpersonal relationships, and professional life.
The causes of mild sensorineural hearing loss
The causes of mild sensorineural hearing loss can be congenital or acquired. Congenital causes are factors that cause sensorineural hearing loss before birth, while acquired causes are those that cause it later in life. The main cause of sensorineural hearing loss is damage to the inner ear. The inner ear houses a spiral-shaped organ called the cochlea. The cochlea contains tiny hair cells called stereocilia. The primary mission of these hair cells is to convert sound waves received from the middle ear into nerve signals transmitted to the brain via the auditory nerve. It is these nerve signals sent to the brain that the brain interprets as understandable sound. The hair cells in the inner ear can be damaged. When this happens, they are no longer able to transmit the correct signals to the brain. Thus, even if the outer and middle ear receive sound and transmit it to the inner ear, this sound cannot be understood because it is not properly routed to the brain. Many factors can damage hair cells, but the most important of these is exposure to loud sounds. Exposure to sounds exceeding 85 decibels can damage hair cells and lead to hearing loss. In most cases, hearing loss only appears when approximately thirty to fifty percent of the hair cells in the inner ear are damaged. In some cases, the hair cells are not damaged: they are simply flattened. You may then experience some hearing discomfort, including tinnitus. But once they straighten up, this discomfort disappears. However, if the hair cells are damaged, there is nothing to be done. The hair cells in the inner ear cannot be repaired, regenerated, or regrown. Any damage to them is permanent, meaning that any hearing loss due to hair cell damage is permanent. Now that we have identified damage to the inner hair cells as the main cause of mild sensorineural hearing loss, let's examine some factors that cause damage to the inner hair cells and the auditory nerve. These can also be considered causes of mild sensorineural hearing loss.
1. Congenital factors
As we have already indicated, mild sensorineural hearing loss can develop before birth. Congenital mild sensorineural hearing loss is hearing loss present at birth. Studies have shown that hearing loss is one of the most common congenital abnormalities. The most common causes of mild sensorineural hearing loss at birth are infections such as herpes or rubella, jaundice, preeclampsia, obstetric trauma, low birth weight, herpes simplex virus, drug or alcohol consumption during pregnancy, prematurity, lack of oxygen, as well as genetic factors or Rh factor incompatibility. In most cases, congenital mild sensorineural hearing loss is permanent. Hearing aids can, however, help the child hear better.
2. Intense noise
There is a limit to how much sound your ears can tolerate. Exposing your ears to sounds above 85 decibels can damage their hair cells and cause sensorineural hearing loss. Exposure to intense noise from industrial tools and equipment, firearms, rifles, grenades, bombs, and explosives can damage your ears. Similarly, listening to music at very high volume with headphones or exposing your ears to the din of bars, nightclubs, and concerts can damage them. Sudden exposure and prolonged exposure to intense noise have the same effect on your hearing. Protecting your ears during noisy activities helps prevent your hair cells from being damaged.
3. Aging
Age-related hearing loss is called presbycusis. As you age, different parts and organs of your body begin to deteriorate or wear out. The hair cells in your inner ear also degrade. This can cause mild sensorineural hearing loss. In addition to the natural aging of hair cells, this degradation can also result from all the years you have exposed your ears to high sound levels. Mild sensorineural hearing loss due to age is incurable. In most cases, it progresses to severe hearing loss. With appropriate medical follow-up and hearing aids, you can, however, continue to function normally.
4. Ear diseases and infections
Ear infections, especially those accompanied by ear pain, fever, and discharge, can cause mild sensorineural hearing loss in both adults and children. If left untreated for a long time, ear infections can lead to permanent hearing loss or even deafness. Autoimmune inner ear diseases can also cause hearing loss. These diseases occur when the body's immune system begins to attack the structures of the inner ear. This attack primarily targets the hair cells of the inner ear. With prompt medical attention, it is possible to preserve some of the hair cells, but if treatment is delayed, all of them can be destroyed, leading to permanent hearing loss.
5. Other causes
Other factors, such as otosclerosis or bone abnormalities of the middle ear, can also cause mild sensorineural hearing loss.
Acoustic neuroma, Meniere's disease, earwax impaction, and head trauma can also lead to mild sensorineural hearing loss.
Treatment for mild sensorineural hearing loss
Currently, there is no surgical intervention to treat mild sensorineural hearing loss. The most common solutions for mild sensorineural hearing loss are hearing aids and cochlear implants.
1. Hearing aids
Hearing aids are devices designed to improve the hearing of people with hearing loss by making sounds audible to them.
In most countries, hearing aids are classified as medical devices: they can only be prescribed by an ENT doctor and fitted by an audiologist. Hearing aids are adjusted according to the specific hearing needs of each person with hearing loss. For example, if you have difficulty hearing high-pitched sounds, the audiologist will adjust your hearing aid to amplify those frequencies without affecting others. There are different types of hearing aids. Some are placed behind the ear, others inside the ear canal.
2. Cochlear implants
A cochlear implant is a small electronic device designed to stimulate the cochlear nerve, which is responsible for hearing. Cochlear implants are surgically implanted to help people with various forms of sensorineural hearing loss. A cochlear implant consists of two parts: an external part and an internal part.
The external part of the implant is placed behind the ear; it is equipped with a microphone that picks up environmental sounds and transmits them to the internal part of the implant. A receiver in the internal part receives the sound from the microphone and sends electrical information to the auditory nerve. Just like hearing aids, cochlear implants are recommended and adjusted by trained audiologists, after appropriate tests have been performed.
Preventing mild sensorineural hearing loss
The only type of mild sensorineural hearing loss that can be prevented is that caused by noise. Apart from this cause, the other factors causing hearing loss are often beyond your control. The best way to prevent mild sensorineural hearing loss due to noise is to protect your ears by wearing protective devices when exposed to loud sounds. You should avoid exposure to intense noise as much as possible. When the noise source is unavoidable, for example in your workplace, always wear protection. Here are some devices you can wear to protect your ears from noise:
Foam earplugs: These can be found in most pharmacies and are accessible to everyone.
Filtered earplugs: These earplugs are ideal for music lovers or musicians who regularly attend musical events such as concerts. They protect your ears from intense noise without altering the quality of the sound or music.
In-ear monitors: These are custom-made devices for musicians. They protect the ears by regulating the volume of sound the user perceives from each instrument and each band member. They are used both during rehearsals and during concerts.
Percussive filters: These devices are custom molded for hunters. They are designed to block the intense noise of gunshots during hunting. Hunters can continue to converse normally while wearing them.
Conclusion
Even if most causes of mild sensorineural hearing loss cannot be avoided, you can still protect your ears by consulting a professional quickly as soon as you notice a hearing problem. The importance of prompt medical attention for hearing disorders cannot be overstated. If mild sensorineural hearing loss is left untreated for a long time, it can worsen and progress to total or profound hearing loss. Do you suffer from mild sensorineural hearing loss? What solution have you chosen? Feel free to share it with us.
