What causes auditory neuropathy? Auditory neuropathy, also referred to as auditory dysynchrony or Auditory Neuropathy Spectrum Disorder (ANSD), is considered to be a hearing disorder in which the quality of sound is distorted, much like listening to a radio station with a bad antenna. There is still some uncertainty about what causes ANSD, but the outer and inner hair cells of the cochlea are cited as the source of the distortion in sound perception.
The effect of ANSD varies widely and the level of hearing can range from normal to severe. However, poor speech perception is a feature of ANSD and may not be correlated with the degree of hearing loss.
ANSD is typically diagnosed using a series of three audiological tests. Otoacoustic emissions (OAE) tests determine the functional level of the outer hair cells. Auditory brainstem response (ABR) tests use electrodes on the heads to detect how the brain or, more specifically, the hearing nerve, is responding to sound. The third test includes testing the middle ear muscle reflex. In the case of ANSD, loud sounds typically do not trigger the reflex.
In summary, ANSD is a complex diagnosis with a significant impact on speech perception, which impacts language acquisition and development. As Cued Speech provides clear, visual access to the language being spoken, it resolves the ambiguity of speech that occurs in the presence of ANSD.