APPLICATION

Auditory Neuropathy Spectrum Disorder

Where the ABR is absent but a present cortical response can still predict speech-perception potential.

What the cortical response shows

  • A present cortical response in ANSD is associated with better speech-perception outcomes, while an absent one predicts poorer aided benefit.[16]
0100200300400latency (ms)Cortical response
In ANSD the brainstem response is absent or grossly abnormal, yet a cortical response — though it may be reduced or delayed — can still be present, indicating cortical detection of sound.

Why the cortical response here

  • ANSD combines normal outer-hair-cell function (present OAEs) with disordered neural synchrony, so the synchrony-dependent ABR cannot be used to estimate thresholds.[16]
  • The cortical response does not require the tight neural synchrony the ABR demands, so it can succeed exactly where the brainstem response fails.[17]

How it changes management

  • The cortical response helps stratify management — supporting amplification or implantation decisions — when behavioural and brainstem measures cannot.[17]

TEACHING POINT

In ANSD, trust the cortex over the brainstem: a present cortical response carries prognostic weight the absent ABR cannot.[16]

Sources for this page are listed on the References page. Browse all applications from the atlas home.