Auditory adaptation: notes on power and parabolic curve fitting across intensity and time. I

The classic procedure for the study of auditory adaptation has been the method of Simultaneous Dichotic Loudness Balance ( SDLB ). Data from four publications ( Jerger , 1957; Palva and Karja , 1969; Weiler , Loeb and Alluisi , 1972 and Weiler and Hood, 1977) were combined to yield values extending from 20 dB to 80 dB average sensation level. A growth curve was fitted to the data by means of the Gompertz curve-fitting technique. A close fit was obtained, and a somewhat closer fit was found using a parabolic curve. In addition to the average data for SDLB adaptation across test intensities, the Gompertz method was used to fit the course of adaptation over time for one additional study ( Thwing , 1955).