Electronic Thesis and Dissertation Repository


Master of Science




Dietz, Mathias


Several studies have reported human threshold interaural time differences (ITDs) near 10 μs; however, none of these studies aimed to find the stimulus and experimental method that yields the lowest threshold. The goal of the current study is to systematically determine the stimulus and the experimental paradigm that yields the smallest threshold ITD and to provide an accurate reference value. We systematically varied seven parameters: stimulus waveform, stimulus level, stimulus duration, adaptive versus constant stimulus procedure, number of reference intervals, inter-stimulus pause duration, and inclusion versus exclusion of onset and offset ITD. The condition yielding the lowest threshold ITD was band-pass filtered noise (20-1400 Hz), presented at 70 dB SPL, with a short inter-stimulus pause of 50 ms, and an interval duration of 0.5 s. The average threshold ITD for this condition at the 75% correct level was 7.0 μs for nine trained listeners and 17.7 μs for 52 untrained listeners.