Auditory Neuropathy

Auditory neuropathy is a hearing condition that makes it difficult to understand speech clearly. If you have this condition, your ear may be able to hear the volume of sound, but there’s a problem when your inner ear tries to send sound signals to your brain via your auditory nerve. About 5 to 10 out of 100 children with hearing loss have this condition.

Another name for it is auditory neuropathy spectrum disorder (ANSD). This is because symptom severity happens on a spectrum, meaning it can be different for one person compared to another. Some children have normal hearing, while others have profound hearing loss (deafness). What’s common is that speech is challenging to understand.

If your child is diagnosed, they may need to wear a device that helps them hear sounds more clearly. They may need speech therapy to learn to communicate. No matter the situation, there’s support available for you and your child.

Symptoms of auditory neuropathy

Children with this condition have trouble with speech perception. They may have hearing loss that shows up differently depending on their age:

• Newborns: Not being startled by loud noises
• At 6 months: Not responding to a parent or caregiver’s voice
• At 12 months: Not babbling, cooing or trying to make basic words, like “mama” or “dada”

Your child may experience their surroundings differently from others. They may:

• Hear sounds but not know what they are or where they’re coming from
• Have hearing ability that fades in and out or changes by the day
• Hear others but be unable to understand what they’re saying
• Be unable to speak or have limited speaking ability
• Have trouble learning

Hearing loss can keep your child from engaging in the world around them as they otherwise would. It can lead to isolation and get in the way of how they grow and develop.

This is why it’s important to let their pediatrician know ASAP if you think there’s an issue.

Auditory neuropathy causes

This condition happens when sound signals don’t travel normally from your child’s cochlea (the hearing organ in their inner ear) to their brain.

Normally, sound waves from the environment travel through the outer and middle ear until they reach the cochlea. Sensory hair cells inside turn the sound waves into signals. The signals travel along the auditory nerve to the hearing part of the brain.

But with auditory neuropathy, there’s a communication breakdown somewhere along the end part of the hearing pathway. There are lots of potential causes or risk factors, including:

• A faulty OTOF gene (the gene that codes for a protein that helps the cochlea work)
• Inherited neurological conditions, like Charcot-Marie-Tooth disease and Friedreich’s ataxia
• Medicines that cause inner ear damage
• Infections, including measles, mumps and cytomegalovirus
• Conditions that impact newborns, like premature birth, low birth weight, low oxygen and neonatal jaundice (many of these conditions involve a stay in the neonatal intensive care unit, or NICU)
• Head injuries

How doctors diagnose this condition

Healthcare providers may find an issue during your newborn’s hearing screening that leads them to a diagnosis. But often, children are diagnosed several months later, when parents start to notice issues. This is because the screening process can miss some cases of auditory neuropathy.

Your child may need to see an otolaryngologist (ENT) or audiologist for a diagnosis. Tests that diagnose auditory neuropathy include:

• Otoacoustic emissions (OAE): This test checks to see how your child’s cochlea is working to receive sound waves. With ANSD, test results are typically normal.
• Auditory brain stem response (ABR): This test checks how your child’s auditory nerve and the hearing part of their brain respond to sound. Usually, the test results are abnormal.
• Middle ear muscle reflex testing (MEMR): Also called acoustic reflex testing, this test shows how well your child's middle ear muscle reflex responds to loud noise. With ANSD, the reflex may not respond at all, or it may require extreme loudness to respond.

Your child will likely need other tests to find possible causes or to diagnose related issues:

• Neurological test: This test can show if auditory neuropathy is one part of a larger neurological condition.
• Vision tests: Hearing and vision problems are sometimes related. Your child will likely need their vision checked to detect any issues.
• MRI: This imaging test can show structural issues or nerve problems that may be causing your child’s symptoms.
• Genetic testing: Your provider may test for genes linked to this condition.

How is ANSD treated?

Hearing assistive devices and speech therapy help most children and their families learn to manage the condition. Treatments include:

• FM systems: These devices require someone who's speaking to wear a microphone that connects wirelessly to a hearing device your child wears. It helps your child make out speech better in noisy environments. These systems can be especially helpful at school.
• Hearing aids: A hearing aid can help boost the volume if your child is having difficulty hearing. Some children benefit from using hearing aids along with FM systems.
• Cochlear implant: A cochlear implant helps many children with sensorineural hearing loss (affecting the inner ear and/or the auditory nerve) hear better. Studies show that this applies to ANSD, too.
• Speech therapy: Lip-reading and sign language can help your child better understand what others are saying and communicate with more confidence. A speech-language pathologist can help teach these and other communication strategies.

When should I see my healthcare provider?

See your child’s pediatrician right away if you suspect your child is having hearing issues. The sooner you contact a provider, the sooner your child can receive the care they need. Early interventions often prevent children from missing out on key developmental milestones related to hearing loss.

What can I expect if my child has this condition?

It can be challenging to predict.

In some cases, auditory neuropathy goes away on its own. Some children begin speaking and interacting like normal within a year or two. Often, cochlear implants help children with auditory neuropathy hear and understand others better.

But cochlear implants don’t work in all cases of ANSD. This is why your healthcare provider will develop a treatment plan for your child that's based on their symptoms.