The left ear responses are  a “shadow curve” – they reflect cross over from the left insert earphone to the right ear, which occurs when the left air-conducted sound becomes bone conducted – the right cochlea is stimulated.

• What is this patient’s interaural attenuation for pure tones using insert earphones?

You often hear that the interaural attenuation value for insert earphones “is 50 dB HL”.

• What is the more correct statement?