**Figure 2:** **The mean performance of human adults in ordering which of
two pure tones (250 vs. 4800 Hz; 250 vs. 300 Hz) came first.** The ordinate
gives the percentage of correct ordering: “higher frequency came first” or
“lower frequency came first”. The abscissa gives the tone onset interval. The
arrows represent the tone interval where the percentage of correct ordering
crosses 75% (called “order threshold”). The order threshold resided around
30 ms, with small variance related to difficulties in frequency discrimination
(Modified from Hirsh [11]). |