Abnormalities of ICP loudness adaptation at 1000 Hz associated with higher frequency (cochlear) loss

Individuals with higher frequency hearing loss, when tested at 1000 Hz, showed more loudness adaptation at 40 dB HL and less at 60 dB HL (ISO) than the normal listeners. Adaptation was measured with the monaural method described by Weiler, Sandman and Pederson (1981), now called the Ipsilateral Comparison Paradigm (ICP) by Dange et al. (1993). Using the same method Korman (1986) had shown that a complex combination of stimulus conditions, including intensity, produced differences between a similar group with high frequency hearing loss and normals. The current results confirm the value of this method for studying adnormalities in the loudness function at middle intensities. Because it is a quick and reliable method we believe it has potential for clinical use but acknowledge considerable research and development is necessary.