A missing audiometric shadow curve reveals feigned (non-organic) hearing loss.
Evidence
The shadow curve is a “false” audiometric curve that occurs because a patient hears a sound in a non-test ear due to bone conduction from the sound presented in a test ear. The amount of sound “crossover” is roughly 0 to 10 dB for bone conduction and 40 to 80 dB for air conduction. A patient with a true, and large, unilateral hearing loss should present with a shadow curve during audiometric testing. The absence of a shadow curve when there should be one is clear evidence of a non-organic hearing loss. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1763
Categorization
- DEFINE: Explains what an audiometric shadow curve is and why its absence signals pseudohypacusis.
- corroborated: 3 independent passages support this claim — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1763
- XREF: connects to: Response bias shifts audiometric thresholds away from a patient’s true hearing abilities