Condition · Neural

Auditory Neuropathy Spectrum Disorder

Dyssynchronous eighth-nerve transmission — reflexes absent, OAEs present

A disorder of neural synchrony

ANSD is characterised by present otoacoustic emissions and/or cochlear microphonic — showing outer hair cell function — with absent or grossly abnormal auditory brainstem responses, indicating disrupted neural synchrony. Acoustic reflexes are absent or markedly elevated.

Why the reflex matters here

The combination — absent reflexes, present OAEs, abnormal ABR — is the diagnostic triad. The reflex contributes the immittance evidence of neural involvement.

The reflex signature

Stim. Right
Stim. Left
Probe Right
Absent
Absent
Probe Left
Absent
Absent
The characteristic four-cell grid for this condition.

All four cells are absent — a globally absent pattern that, with present OAEs, is highly suggestive of ANSD.

Reflex decay

0s2s4s6s8s10s0%50%100%50% criterion
Negative (normal) decay — amplitude is well maintained across the 10-second hold. Reflexes are characteristically absent, so decay cannot be measured.

Pure-tone audiogram

0204060801002505001k2k4k8kFrequency (Hz)Hearing level (dB HL)
○ Right ear✕ Left ear
Variable audiogram — often a mild-to-moderate loss disproportionate to the very poor speech perception.

Frequencies plotted: 250, 500, 1k, 2k, 4k, 8k Hz.

References for this page

  1. Starr A, Picton TW, Sininger Y, Hood LJ, Berlin CI (1996). Auditory neuropathy. Brain, 119(3), 741–753.
  2. Katz J (Ed.) (2015). Handbook of Clinical Audiology (7th ed.). Wolters Kluwer, Philadelphia.
  3. Hall JW (2014). Introduction to Audiology Today. Pearson, Boston.
Want to contrast this with another condition? The comparison tool places any two reflex signatures side by side.