RECALIBRATING THE PERCEPTION OF LOUDNESS - INTERAURAL TRANSFER

Previous research, using both magnitude-scaling and direct-comparison methods, has shown the perception of loudness to be contingent on the distribution of tonal stimuli varying in sound frequency as well as SP L: When a low-frequency signal, f(1), is presented at low SPLs and a h igh-frequency signal, f(2), at high SPLs, loudness at f(1) is great re lative to that at f(2); reversing the association of SPL with frequenc y reverses the loudness relation. These shifts in relative loudness, r ecently termed ''recalibration'' [Marks, J. Exp. Psychol. 19, 227-249 (1994)], are consistent with the operation of frequency-specific, fati guelike processes at f(1) and f(2). Experiment 1 combined both scaling (magnitude estimation) and matching (direct-comparison) methods and s howed that exposing one ear to recalibrating stimuli (500 and 2500 Hz) led to substantial shifts not only in the ipsilateral ear but also in the contralateral ear (albeit smaller ones). Experiment 2 used a sele ctive-exposure procedure and gave similar results. Thus the processes underlying recalibration of loudness appear to involve central mediati on; consequently, it is possible that processes of auditory fatigue re ly on central as well as peripheral mechanisms. (C) 1996 Acoustical So ciety of America.