Temporal window shape as a function of frequency and level

Abstract

The temporal window is an intensity weighting function that processes the internal representation of auditory stimuli by integrating energy over time. Temporal window shapes were measured using the technique described in an earlier article [Moore et al., J. Acoust. Soc. Am. 83, 1102–1116 (1988)]. Window shapes were measured at four different frequencies (300, 900, 2700, and 8100 Hz) and at three different masker levels covering a 20‐dB range at each frequency. The shape of the temporal window was well described by modeling each side as the sum of two rounded‐exponential functions. The equivalent rectangular duration (ERD) of the window was roughly constant at about 8 ms for center frequencies from 900 to 8100 Hz, but increased to about 13 ms at 300 Hz. The increase at 300 Hz may be explicable in terms of “ringing” in the auditory filter. The ERD decreased somewhat with increasing level, for example, having a value of about 10 ms at 2700 Hz with a 20‐dB masker spectrum level and about 7 ms with a 40‐dB masker spectrum level. Temporal window shapes can be used to produce temporal excitation patterns that illustrate the effect of limited temporal resolution on the internal representation of acoustic stimuli. [Work supported by MRC, UK.]