INTERPRETATION OF ABLB TEST:
a) Absence of Recruitment :- (i.e no abnormal growth of loudness) This occurs when there is equal loudness at equal sensation levels. An example will calrify this. Suppose that left ear has a hearing threshold level (HTL) of 40dB at a particular frequency , and the right ear is normal i.e 0dB HTL at that frequency. If therte is no recruitment , then a 50dB hearing level sound on the left ear will appear equal in loudness to a 10dB HL sound on the right ear, a 70dB HL sound on the left ear will be equal loudness to a 30 dB HL sound on the right ear and 100dB HL sound on the left ear will correspond thta for equal loudness level in the two ears , the difference in the hearing will remain constant (40dB in this case )no matter what be the intensity of the sound . an allowance of +- 10dB is acceptable i.e in the foregoing even if the sound of 100 dB in the left ear was equal in loudness to a sound of 50dB or 70Db ( instead of 60 dB ) in the right ear it would yet be accept as a case of no recruitment or absence of recruitment.
