APPLICATION

Non-organic Hearing Loss

The reference objective test when the behavioural audiogram is exaggerated — including medicolegal claims.

What the cortical response shows

  • A repeatable cortical response present at levels markedly better than the volunteered thresholds confirms a non-organic component and estimates the true threshold to within about 5–10 dB.[6]
0100200300400latency (ms)Stimulus at 40 dB HL
A clear cortical response is recorded at a level well below the claimed behavioural threshold — objective evidence that hearing is better than reported.

Audiogram companion

The pure-tone audiogram below accompanies the scenario. Reading the volunteered thresholds against the objective cortical result is the core skill on this page.

0204060801002505001k2k4k8kFrequency (Hz)
○ Right — PTA 65 dB (Moderately severe)✕ Left — PTA 63 dB (Moderately severe)
Pure-tone audiogram companion. dB HL increases downward, following clinical convention. Illustrative thresholds — not recorded patient data.

Why the cortical response here

  • The obligatory cortical response cannot be voluntarily suppressed and gives frequency-specific thresholds in an awake adult, so it directly tests the claimed audiogram.[5]
  • It is the most direct objective analogue of the behavioural audiogram, which is why it is favoured over the ABR for adult medicolegal threshold confirmation.[7]

How it changes management

  • The objective cortical threshold becomes the reported threshold for medicolegal purposes; the discrepancy with the behavioural test is documented rather than the patient confronted.

TEACHING POINT

A cortical response at a level the patient denied hearing is the cleanest objective demonstration of non-organic exaggeration available in an awake adult.[5]

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