EFFECT OF SEQUENCE DELAY ON THE DISCRIMINATION OF TEMPORAL PATTERNS

This experiment tested listeners' ability to discriminate between two temporal patterns as a function of the time interval between the patte rn onsets. The listener's task was to decide whether two arrhythmic se quences of nine tones had the same or different temporal patterns; the patterns were defined by the time intervals between the tones. Accord ing to the temporal pattern correlation model [R. D. Sorkin, J. Acoust . Soc, Am, 87, 1695-1701 (1990)], listeners extract information about the series of time intervals in each sequence and then compute the cor relation between the two series. In the present experiment, the tones in the second sequence were presented at a different frequency than th e tones in the first sequence. In one condition, all time intervals in the second sequence were compressed or expanded by a factor that vari ed randomly over trials. Performance was very good when the sequences did not overlap in time, but was poor when the sequences overlapped. P erformance was generally consistent with a discrimination mechanism th at cannot process more than one pattern at a time.