Temporal Order and Perceptual Classes

Continuing our work on temporal order perception, we have measured the duration of four equal segments in a continuously repeated sequence of four pure tones necessary for correct perception of their temporal order. When all four tones were within a musical fourth (critical band?) the segment duration necessary for correct order perception was 125 msec—the same as we obtained earlier for natural vowels. However, when the tones were more widely spaced in frequency, the duration of each segment necessary for correct order perception was considerably greater (up to 500 msec) depending on the specific distribution of pure tones. Likewise, for a mixture of “different” stimuli (e.g., pure tones, white noise, etc.) segment durations again were considerably greater than 125 msec for correct order perception. It appears from these tests that much of the segment time in excess of 125 msec necessary for correct order perception results from the need to shift attention among “different” classes of stimuli. [Work supp...