Hearing loss is a common, age-old problem for many people; one in eight over the age of 12, to be exact. What was once thought to be a sign of old age, is now known to occur at any age, and to anyone.
The problem is common, but not all types of hearing loss are created equal. The four main types of hearing problems are:
Though all four types of hearing difficulties result in the same outcome, it’s important to know what they are, how they can affect you, and what your treatment options are. Let’s dive in.
Sensorineural Hearing Loss
The inner ear is formed in a snail-like shape, called the cochlea. The cochlea is filled with tiny hair cells that change sound vibrations into electrical signals that are transmitted to the brain through the hearing nerve. When these hair cells or the nerve that connects the brain to the ear are damaged, you will experience sensorineural hearing loss (SNHL).
SNHL is the most common type of hearing loss, affecting roughly 9 out of 10 people with hearing problems. It usually affects both ears and can range in severity from mild to severe. Sensorineural hearing loss is lifelong and cannot be reversed.
SNHL is caused by many things, including the natural aging process. While sensorineural hearing loss usually occurs later in life, it can begin at any time. There are several causes for SNHL.
Presbycusis
A fancy word for age-related hearing loss, presbycusis affects one in three Americans aged 65-74. The loss of hearing is gradual, and usually in both ears, causing the loss to often go unnoticed in its early stages. Typically, presbycusis begins with losing the ability to hear high pitched sounds. This results in the hearer being unable to distinguish between certain parts of speech, such as /s/ and /th/, and complaining that others are “mumbling”. Though the speech is loud enough, it’s the pitch in the speech that is the problem.
Most people buying (or needing) hearing amplifiers suffer from presbycusis. If this describes your problems, take a look at our overview of hearing amplifiers.
Noise Induced Hearing Loss
Noise Induced Hearing Loss (NIHL) is a form of SHNL that comes from hearing a loud noise suddenly or over a long period of time. Any noise exposure over 85 decibels (dBA) can damage your hearing. The longer you’re exposed to these sounds, the higher the risk of (more) damage.
As most people know, sudden noise exposure can cause damage to your hearing. This happens when you’re exposed to sudden, loud noises such as explosions or nearby gunfire. If your ears are ringing, your hearing is damaged. It’s best to avoid these environments whenever possible.
While loss of hearing due to sudden noise exposure may not surprise most people, you may be surprised to hear that prolonged exposure to everyday, seemingly harmless things can cause just as much damage. For example, the volume in a movie theater can reach up to 104 decibels. Music through headphones on maximum volume, concerts, and sporting events have a volume of 94-110 dBA.
While these things may not seem as damaging for your ears as a gunshot (up to 190 dBA), over a period of time, exposure to such high decibels slowly damage and then deaden the nerves in the ear. This causes gradual hearing loss.
Serious viral infections
Viral infections such as meningitis, measles, and mumps can cause sensorineural hearing loss. These infections can cause inflammation of the inner ear or auditory nerve, resulting in the sudden onset of SNHL. Some patients are able to recover their hearing without any intervention, but most seek treatment from a medical professional. Treatment includes a steroid, usually Prednisone, that results in an expected recovery rate in approximately 60% of patients.
Physical injuries to the ears or head
Head injuries can be serious, with Traumatic Brain Injury (TBI) accounting for 2.8 million injuries in the United States per year. While TBI can cause sensorineural hearing loss, it can sometimes go unnoticed in the wake of an injury.
When TBI occurs, the damage can affect the auditory pathway; anywhere from the outer ear to the auditory cortex in the brain. This can lead to SNHL. The hearing loss associated with TBI can fluctuate over the entire year following the injury.
Conductive Hearing Loss
Conductive hearing loss (CHL) occurs when the outer ear, middle ear, or eardrum have difficulty transmitting sound waves to the brain. Unlike sensorineural hearing loss, conductive hearing loss can often, but not always, be reversed with surgery or pharmaceuticals.
CHL prevents the sound waves entering the ear from making it through to the inner ear, which sends sounds to the brain for processing. This can make it difficult to hear soft sounds, and loud noises may be muffled. CHL may occur in one or both ears.
Common causes of conductive hearing loss include:
- Fluid in the middle ear caused by an illness or allergies
- Ear infection
- Improper drainage of the euchastian tube from the middle ear
- A hole in the eardrum
- Tumors in the ear canal. These tumors are usually benign, but can block the sound from entering the inner ear.
- Earwax
- Swimmer’s Ear- When fluid gets stuck in the ear canal and becomes infected.
- A foreign object stuck in the outer ear
- A deformity with the ear
Most of the time CHL can easily be treated with help from a medical professional. Sometimes surgery may be required. If the issue cannot be treated, use of hearing devices can be highly effective.
Mixed Hearing Loss
When both sensorineural hearing loss and conductive hearing loss are present, you will receive a diagnosis of mixed hearing loss. Head injury, long-term illness, and DNA can cause problems with both the inner ear and the middle or outer ear.
Luckily, through modern technology, you no longer have to sit around with a horn in your ear to find out what’s happening around you. For a list of the highest recommended hearing amplifiers, click here.
Auditory Processing Disorder
Auditory Processing Disorder (APD), also known as Central Auditory Processing Disorder (CAPD), is a hearing disorder that affects roughly 5% of school aged children. Though APD typically begins in childhood, it is present in many adults.
APD is not related to other types of hearing loss, as the pathways and mechanisms in a person with Auditory Processing Disorder are fully functioning and healthy. Rather than the hearing loss being caused by damage, there is actually a misunderstanding in the way the brain processes the sounds it hears.
When sound waves enter the ear of someone with APD, those tiny hair cells we talked about before try to send these signals to the brain through a nerve. However, when the brain receives the information, it does not compute. The brain simply cannot register all of the sounds it hears.
This misunderstanding leads to a lot of confusion for the hearer, often resulting in behavioral issues and problems with learning in an otherwise bright and well-behaved child.
Though there is no clear cause for APD, doctors believe it can be caused by:
- Illness- Multiple ear infections, meningitis, lead poisoning, and nervous system diseases can lead to APD.
- Premature birth or low birth weight
- Head injury
- Genes
Early treatment for APD is critical. When left unchecked, APD can cause speech delays, social difficulties, and problems at school or work. APD sometimes shares symptoms with other issues, making diagnosing APD a challenge. It can’t be diagnosed through a symptoms checklist, but through testing from an audiologist.
Treatment for APD happens on a case-by-case basis. The needs of an individual depend on the environment. From there on, changes can be made. For example:
- In an environment that requires concentration, a person with auditory processing disorder should sit away from objects that make a lot of continual noise.
- Using better communication practices, like talking slower and taking frequent breaks to give the hearer time to “register” what is being said.
- In a classroom setting, a microphone and headset help allowing the child to tune out background noise and focus only on the teacher’s voice.
Not all types of hearing loss have a solution. Sometimes, a surgical intervention is necessary. Other times, a hearing aid or hearing amplifier can help combat the effects of hearing loss. Hearing aids are prescribed by an audiologist and best suited for complex cases of hearing loss. Age-related hearing problems are often helped with hearing amplifiers (a hearing device that’s only a fraction of the price of a hearing aid). For more information on the difference between hearing aids and hearing amplifiers or hearing amplifiers in general, please see our articles.
Would you like to make better-informed buying decisions? Sign up to our newsletter below and get personalized buying advice, information about life with hearing loss, and the latest information directly to your email.