(AN; Auditory Dyssynchrony; Auditory Synaptopathy; Neuropathy, Auditory; Auditory Processing Disorder)
Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention
Auditory neuropathy (AN) occurs when the nerve system of the inner ear fails to process sounds coming from the outer ear.
The outer ear sends vibrations to the inner ear during the hearing process. Hair cells in the inner ear break down the vibrations into electrical signals. These are sent to the brain. The brain filters them as sound. There is debate about the exact cause of AN. It may be due to:
- Damage to the hair cells in the inner ear
- Bad connections between the hair cells in the inner ear and the nerve to the brain
- Damaged nerve
- A mixture of these problems
These factors increase your chance of developing AN:
- Family history of hearing loss
- Lack of oxygen at birth
- Very low birth weight
- Gilbert's syndrome (a genetic disorder) that requires a blood transfusion
- Neurological disorders (eg, Charcot-Marie-Tooth Syndrome, Friedreich’s ataxia)
- Infectious disease (eg, mumps)
- Immune disorders
- Exposure to chemicals or medicines (eg, aminoglycosides, loop diuretics) that cause hearing loss
- Neurofibromatosis type 2 (genetic disorder of the nervous system)
Tell your doctor if you or your child has any of these risk factors.
If you have any of these symptoms do not assume it is due to AN. These symptoms may be caused by other conditions.
- The sound is heard, but the word is not clear (white noise)
- Sounds tune in and out
- Words and sounds seem out of sync
- Tinnitus (ringing in the ears)
The level of hearing loss can vary from mild to severe. People with AN may have trouble picking out words. Many cases involve children.
Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include:
- Auditory brainstem response (ABR) to measure brainwave activity
- Otoacoustic emissions (OAE) to record how the cells in the ear respond to clicking sounds
Talk with your doctor about the best treatment plan for you. Treatment options include the following:
Working with a team of specialists, including:
- Otolaryngologist (ENT)—doctor specializing in disorders of the ear, nose, and throat
- Audiologist—doctor specializing in hearing loss
- Speech-language pathologist—healthcare professional who specializes in communication disorders
Using technology, such as:
- Cochlear implants —surgically implanted electronic devices that stimulate the auditory nerve to send information to the brain
- Hearing aids
- Listening devices (eg, frequency modulation [FM] systems)
Having speech-language therapy, such as:
- Sign language
- Speech-reading (also known as lip-reading)
- Exercises combining listening skills with technology
Goals of treatment include:
- Saving current hearing skills
- Restoring lost hearing
- Finding new ways of communicating
American Speech-Language-Hearing Association
National Institute on Deafness and Other Communication Disorders
Canadian Association of Speech Language Pathologists and Audiologists
Ontario Association for Speech-Language Pathologists and Audiologists
Auditory neuropathy. National Institute on Deafness and Other Communication Disorders website. Available at: http://www.nidcd.nih.gov/health/hearing/neuropathy.asp. Published March 2003. Accessed November 28, 2012.
Causes of hearing loss. My Baby’s Hearing website. Available at: http://www.babyhearing.org/HearingAmplification/Causes/Neuropathy.asp. Accessed November 28, 2012.
Cochlear implants. American Academy of Otolaryngology website. Available at: http://www.entnet.org/HealthInformation/cochlearImplants.cfm. Updated January 2011. Accessed November 28, 2012.
Ototoxicity. American Academy of Otolaryngology website. Available at: http://www.entnet.org/Practice/policyOtotoxicity.cfm. Published December 2006. Accessed November 28, 2012.
Last reviewed November 2012 by Rimas Lukas, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.