Hearing loss is something that most of us don’t think about until we are older, but it can occur at any age. The ear is full of delicate organs that can easily get damaged if they are exposed to loud noises, trauma, or infections.
Although there are lots of different things that can cause hearing loss, the most common form is age-related hearing loss. This describes the reduced capability to hear mainly high-frequency noises, and it affects millions of older people across the world at any one time.
Whether caused by genetics, hereditary conditions, trauma, or infection, hearing loss can severely impact a person’s quality of life. It can make basic interactions difficult for the individual and may cause them to feel excluded from society.
Somebody who is born without full hearing will have a genetic condition that has impacted the development of the ear. If hearing is lost through the course of somebody’s life, it is referred to as acquired hearing loss.
Hearing loss can range in severity from mild to severe, regardless of the age of the individual. The cause of the hearing loss can impact the severity of the condition, and it also impacts the types of treatments that are available.
The best hearing aids can often be sufficient for those who have partial hearing loss. For others, a more invasive form of treatment might be required, such as a cochlear implant. Assisted listening devices can improve the individual’s quality of life by making communication easier.
Structures in the Ear
Before we learn about the common causes of hearing loss across the globe, it’s important to know more about the anatomy of the ear. Different causes of hearing loss can impact different parts of the ear.
The ear is split into three parts – the outer, middle, and inner ear. Each of these three areas of the ear works closely together to collect sound waves. The sound waves are converted into electrical impulses that are sent to the brain for interpretation.
Normally, this whole process takes just a few milliseconds and enables you to hear what is going on around you at all times. In somebody who is deaf or hard of hearing, one or more of these areas within the ear are dysfunctional.
So, what are the functions of each area of the ear?
- Outer ear – this is the portion of the ear that is visible on the outside. It forms a circular shape to capture as many sound waves as possible and reflect them towards the eardrum.
- Middle ear – separated from the outer ear by the eardrum, the middle ear consists of three tiny bones (the malleus, anvil, and stapes bones). These bones absorb the sound waves that are entering the ear and vibrate at a specific frequency to transmit the sound into the inner ear. A structure known as the Eustachian tube helps to equalize the air pressure within the middle ear.
- Inner ear – the inner ear is the deepest part of the ear and it contains a structure called the cochlea. The cochlea has a spiral shape that converts sound waves into electrical signals that are sent to the brain for interpretation.
Causes of Hearing Loss
There are multiple causes of hearing loss, some of which people are born with and others that happen over the course of somebody’s life. Let’s go through each of these common causes of hearing loss and why they occur.
Aging is one of the most common causes of hearing loss. It results from the slow degeneration of the cells and nerves in the ears. Older people don’t always completely lose their hearing but they can become less efficient at collecting and interpreting sound waves. As a result, their hearing becomes impaired.
Age-related hearing loss usually begins with a reduction in the ability to hear high-pitched noises. An older person might struggle to hear somebody screaming or they might no longer be able to listen to the birds chirping in the morning.
Another common symptom of age-related hearing loss is the inability to distinguish between the letters ‘d’, ‘f’, and ‘s’. These consonants sound very similar and somebody who has age-related hearing loss might no longer be able to tell the difference between them.
Most older people who are hard of hearing will be offered a hearing aid to improve their ability to interpret sound waves. There are other assisted listening devices, such as amplifiers, speakers, and implants available too.
There are a few genetic conditions that can disrupt the normal development of the ear in utero, such as Patau syndrome and Treacher Collins syndrome. Certain mutations can lead to malformation of one of the structures in the ear, making the individual partially or completely deaf from birth.
Exposure to Viruses or Bacteria
Some diseases can cause infections in the ear, which result in deafness or hearing loss. Common pathogens that can lead to problems with hearing are those responsible for the flu, mumps, meningitis, and chickenpox.
Even if the mother is exposed to some of these viral or bacterial infections during pregnancy, the growing fetus and the newborn’s health might be affected. If a mother falls ill while she is pregnant, the growth and development of the fetal ears might fail to complete.
Trauma to the Ear
Trauma can involve a range of different things. If somebody receives a nasty blow to the head, it can perforate the eardrum or cause damage to the tiny, delicate bones in the middle ear, resulting in hearing loss.
If somebody falls over, is hit by a falling object, or gets into a severe car crash, they can experience mild to severe hearing loss, or even deafness in some cases.
Trauma can also be caused by exposure to loud noises, either acutely or chronically. For example, working on a construction site without protective earwear can cause gradual damage to the ear. Regularly going to very loud concerts or playing your music on a very high volume through earphones can have the same negative effects on your hearing.