Masked thresholds spike within milliseconds of masker onset before settling

Evidence

Within the range of simultaneous masking, additional effects exist shortly after the masker is switched on. The inset of Fig. 4.20 shows the temporal structure used for such an experiment. A high-frequency test tone (5 kHz) is used to produce short test-tone bursts. The masker burst is obtained from white noise and is long, relative to the duration of the test-tone burst. For a masker density level of 20 dB, the masked threshold is indicated in Fig. 4.20 as a function of the duration of the test-tone burst. If the test-tone burst is presented 200 ms after the onset of the masker, then no difference occurs in the dependence of the threshold on duration relative to what is known for the steady-state condition of the masker. For a very small value of ilt, i.e. 2 ms, the masked threshold for short durations shows a strong deviation from the expected behaviour: it rises by up to 10 dB at 2 ms. Such increments can be measured only for durations shorter than about 10 ms. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 508

Categorization

• DEFINE: Introduces the temporal-onset effect in simultaneous masking that motivates the overshoot terminology.