Auditory neuropathy is a hearing disorder in which sound enters the cochlear normally but the transmission of signal from the cochlea to the brain is impaired. Auditory neuropathy is also known as auditory dys-synchony.

From researches, auditory neuropathy may have normal hearing or hearing loss ranging from mild to profound hearing loss. For those who have normal hearing but having auditory neuropathy, they can hear sound but may have trouble in identifing and understanding speech.

Risk factors for auditory neuropathy

There are several factors contributed to the Auditory Neuropathy in children. However a clear cause and effect relationship has not been proven. Some cases of auditory neuropathy can occur in the absence of any medical problem or it can be associated with variety of symptoms and conditions.

The risk factors for auditory neuropathy include

• Jaundice

• Anoxia – absence of oxygen to the organ and tissues

• Infectious process – example, Mumps

• Premature baby

• Genetic factor

• Syndromes such as Charcoat-Marie-Tooth sindrom dan Ehrles-Danlos sindrom

Diagnosing auditory neuropathy

Hearing screening programme is a programme that has been conducted in most of the hospital for early detection of hearing loss. It is also an effort to identify babies with auditory neuropathy.

A test battery for auditory neuropathy includes auditory brainstem response (ABR) and otoacoustic emission (OAE).

Auditory Brainstem Response (ABR) is an objective test to estimate hearing sensitivity and assess the integrity of auditory nerve. This test is conducted by placing headphone on person’s ears and the responses of auditory nerve are recorded via electrodes placed on the scalp.

Otoacoustic emission (OAE) is a test to identify the integrity of hair cell in the cochlear (organ of hearing). A normal OAE reading is a sign that the hair cells are working normally. The response of hair cells was recorded by placing a probe in the ear that producing a sound.

Auditory neuropathy is diagnosed when person has normal OAE reading but absent or abnormal Auditory Br ainstem Response. Therefore from OAE and ABR results indicated that hair cell of cochlear is intact but the transmission of auditory nerve to brain is impaired.

Treatment and intervention for auditory neuropathy

There are a few treatment and intervention options for Auditory Neuropathy. However the potential benefit of treatment and intervention are vary to individual.

Frequency modulation (FM) systems

Some professionals reported frequency modulation (FM) systems are helpful for auditory neuropathy with normal hearing. Frequency modulation (FM) system is a device that can transmit sound directly to the listener by sound wave. By using FM system, the listener could concentrate to the speech better and would be useful especially in noisy environment.

Hearing aid

However, for auditory neuropathy with hearing loss ranging from mild to severe, hearing aid might give benefit by amplify the speech sound and help them to hear better.

Cochlea implant

Cochlea implant may also help some people with auditory neuropathy especially for case of severe to profound hearing loss. Cochlea Implant is an operation to insert electronic device in the cochlear to compensate the function of the cochlea for those with severely profound hearing loss.Cochlear implants can give auditory neuropathy sufferer the ability to recognize auditory signals.However; no tests are currently available to determine whether an individual with auditory neuropathy might benefit from a hearing aid or cochlear implant.

Professionals believe that combination of listening skills together with technologies such as, hearing aids and cochlear implants is a good approach that may give better understanding to child with auditory neuropathy.

Where can I get more information?

You can get more information regarding auditory neuropathy from

• Audiologist

• Doctor and specialist Ear, Nose and Throat (ENT).

• Speech therapist

Reference

1. Yvonne Sininger, & Arnold Starr (2001). Auditory Neuropathy; A new perspective on hearing disorders. Canada: Singular.

2. National Institute on Deafness and Other Communication Disorders. 2011. Auditory Neuropathy. Retrieved July 4, 2013 from http://www.nidcd.nih.gov/health/hearing/pages/neuropathy.aspx

3. National Institute on Deafness and Other Communication Disorders. 2011. Cochlear Implant. Retrieved July 4, 2013 from http://www.nidcd.nih.gov/health/hearing/pages/coch.aspx

4. Roush, P(2008) Auditory Neuropathy Spectrum Disorder, Evaluation and Management. The Hearing Journal61 (11): 36–41.

5. C. Dunkley, A. Farnsworth, S. Mason, M. Dodd, K. Gibbin (2003).Screening and follow up assessment in three cases of auditory neuropathy. Retrieved from http://adc.bmj.com