When the garbage truck rumbles down the street or thunder claps during a rainstorm, do you hear it? How about the bass notes of a music track? While it’s not very common, some people struggle to hear low-pitched sounds; if you do, it may be due to low-frequency hearing loss.
Low-frequency hearing loss is a fairly rare form of hearing loss that affects the ability to hear lower-pitched or deeper sounds. Some people who have difficulty hearing low tones can’t hear any sounds below 2,000 Hz, while others simply have a harder time with those sounds.
Low-frequency hearing loss will show up as a reverse slope on an audiogram, showing that you have difficulty or an inability to hear pitches on the low end of the human hearing range (20-200 Hz), or even in the medium-low range of 200-2,000 Hz. (Medium pitches are in the 200-5,000 Hz range, while high pitches are 5,000-20,000 Hz.)
Low-frequency hearing loss symptoms include difficulty or an inability to hear low-pitch sounds, such as:
There are two main types of low-frequency hearing loss: sensorineural and conductive. Which type a person deals with depends on the cause underlying the hearing loss.
The cause of low-frequency hearing loss depends on the type of hearing loss you’re experiencing. Sensorineural hearing loss is typically caused by damage or injury that interferes with the signals traveling from the inner ear to the brain along the auditory nerve, interrupting the hearing process.
Conductive hearing loss, in contrast, is generally caused by something preventing the conduction of sound—like a wax or fluid blockage or a physical deformity. Learn more about these two types of hearing loss, and the diseases and conditions that can cause them, below.
Ramsay Hunt syndrome is caused by a shingles outbreak that affects the facial nerves near one of your ears. In addition to the shingles rash itself, Ramsay Hunt syndrome can cause facial paralysis on one side of the face (resulting in one eye and side of your face to droop) and hearing loss in the affected ear. While these symptoms are all generally temporary, prompt treatment can reduce the risk of long-term effects.
The root cause of Ramsay Hunt syndrome is the chickenpox virus (varicella-zoster virus); if you’ve had chickenpox, the virus remains in your body. For 1 in 3 Americans, the chickenpox virus will reactivate later in life, resulting in shingles, with Ramsay Hunt syndrome being a complication of shingles.
Mondini dysplasia, also known as Mondini syndrome or a Mondini malformation, is a congenital inner ear malformation where the cochlea only has one and a half coils rather than two, resulting in hearing loss from birth. This can occur in one or both ears.
Some cases of Mondini dysplasia hearing loss only involve low-frequency sounds, but in most cases the hearing loss is profound. Mondini dysplasia can be diagnosed by a CT scan; many people successfully treat this type of hearing loss with hearing aids or a cochlear implant.
Cerebrospinal fluid surrounds and cushions the spinal cord and brain, protecting it from injury. A tear in the dura matter surrounding the spinal cord and brain can cause a leak, resulting in decreased cerebrospinal fluid pressure. Low cerebrospinal fluid pressure headaches are the most common symptom, but this decrease in pressure can also cause endolymphatic hydrops, resulting in low-frequency hearing loss. Other symptoms may vary. Causes of low spinal fluid pressure can include:
While some cerebrospinal fluid leaks can heal with bed rest, many require surgery to patch and repair the leak.
Sudden sensorineural hearing loss (SSHL), or sudden deafness, is the rapid loss of hearing, either all at once or over the course of several days. It is caused by an issue with the sensory organs in the inner ear. With SSHL, it’s common to only experience sudden hearing loss in one ear, and some types only affect low or high pitches rather than experiencing a total loss of hearing. Tinnitus, dizziness and a feeling of fullness in the ear are often accompanying symptoms.
Sudden hearing loss is rarely permanent; in fact, about half of people with SSHL spontaneously recover their hearing, while others experience recovery through treatment from their doctors. Prompt diagnosis and treatment is recommended to experience the best outcome. The chances of full recovery are higher in those with low-frequency SSHL vs. high-frequency SSHL.
Conductive hearing loss is a type of low-frequency hearing loss caused by a problem—often in your middle ear, ear canal or outer ear—that prevents the conduction of sound into your ear. Secretory otitis media and otosclerosis are two common causes of conductive hearing loss. Learn about both issues, below.
Secretory otitis media, also known as serous otitis media, is when mucus or liquid in the middle ear blocks the eustachian tubes—often a result of an unresolved infection or allergies. This condition primarily occurs in children, causing pressure and discomfort, along with mild to moderate hearing loss.
Low-frequency sounds tend to be reduced first, before high-frequency sounds. While secretory otitis media generally resolves on its own, treatment may be required if it persists longer than three months. At this point, a doctor may consider suctioning out the fluid and placing pressure equalization (PE) ear tubes to encourage ventilation of the middle ear so that fluid does not build up.
Otosclerosis is a condition characterized by the abnormal growth of bone tissue in the bones of the middle ear that ultimately makes the stapes bone become stationary rather than vibrating in response to sound waves. The vibration of the three tiny bones in the middle ear is an essential step in the processing of sound—amplifying sound waves and sending them to the cochlea.
Otosclerosis symptoms include hearing loss, tinnitus and vertigo. Gradual hearing loss is generally the first symptom, often starting just in one ear, with most people first struggling to hear low-pitched sounds. Surgery can help treat this condition, and hearing aids can help hearing loss.
A low-frequency hearing loss diagnosis can be made with a hearing test, with results visualized on an audiogram. This test can be conducted by an audiologist or hearing instrument specialist. If it’s suspected that your hearing loss is related to another condition, like one of those explored above, your hearing care professional or doctor may recommend additional tests.
Treatment for low-frequency hearing loss depends on the root cause. Some hearing loss resolves on its own as the condition, such as secretory otitis media, improves. Other types of low-frequency hearing loss may reverse as the underlying condition is treated, as in the case of low cerebrospinal fluid pressure. For irreversible hearing loss, certain devices, therapies, and lifestyle changes can help.
The best way to treat permanent low-frequency hearing loss, no matter the cause, is with hearing aids. Your hearing care professional can conduct appropriate hearing tests to measure your hearing loss, then help you find hearing aids for low-frequency hearing loss that are programmed to amplify low-frequency sounds. Miracle-Ear has a variety of hearing aid types and styles to meet both your hearing and lifestyle needs.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6331312/
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6215849/
