Auditory Neuropathy

Auditory neuropathy (AN) occurs when the nerve system of the inner ear fails to process sounds coming from the outer ear.

  • Causes

    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

  • Definition

    Auditory neuropathy (AN) occurs when the nerve system of the inner ear fails to process sounds coming from the outer ear.

    The Ear
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  • Diagnosis

    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

  • Prevention

    In many cases, the exact cause of AN is unknown. However, these steps may help:

    • If you are pregnant, ask your doctor how you can avoid infections
    • Talk to your doctor if you have any conditions related to AN

  • Risk Factors

    Factors that may increase your chance of developing AN include:

    • Family history of
      hearing loss
    • Lack of oxygen at birth
    • Very low birth weight
    • Jaundice after birth
    • Gilbert's syndrome—a genetic disorder

    • Neurological disorders such as
      Charcot-Marie-Tooth Syndrome
      Friedreich’s ataxia

    • Infectious disease, such as
      or meningitis
    • Immune disorders
    • Exposure to chemicals or medications that cause hearing loss, such as aminoglycosides, loop diuretics, and some chemotherapies
    • Tumors of the nerve or those that compress the nerve
    • Neurofibromatosis type 2—genetic disorder of the nervous system and skin
    • Trauma

  • Symptoms

    AN may cause:

    • White noise—the sound is heard, but the word is not clear
    • Sounds to tune in and out
    • Words and sounds to seem out of sync
    • Ringing in the ears—tinnitus

    The level of hearing loss can vary from mild to severe. People with AN may have trouble picking out words. Many cases involve children.

  • Treatment

    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 such as 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