Abstract:

Presenting loud tones at one frequency and quiet tones at a different frequency makes the quiet tones appear relatively louder. This phenomenon, dubbed loudness recalibration [Marks, J. Exp. Psychol. 20, 382--396 (1994)], was studied using an adaptive, two-track loudness comparison procedure. In this study, a baseline loudness comparison was initially established between two tones. Immediately following this baseline sequence, a sequence of trials were given in which the two comparison tones were preceded by a recalibration tone. The amount of steady-state loudness recalibration was measured as a function of the recalibration tone level and the baseline comparison tone level. The results showed that loudness recalibration is present when the recalibration tone level is much larger than the comparison tone level and that no loudness recalibration is generated when the recalibration tone level is less than or equal to the comparison tone level. In addition, it was found that a recalibration tone did not affect the threshold level of detection. These results support those of Marks [J. Acoust. Soc. Am. 100, 473--480 (1996)] indicating that loudness recalibration is a centrally based, fatiguelike phenomenon. [Work supported by a Program Project Grant from NIDCD.]