Effect of Structured Contextual Tones on Psychophysical Frequency Discrimination

摘要

Six musically and six non-musically trained observers listened to patterns composed of 11 tones of short duration (40 ms). Using a same-different psychophysical procedure observers were asked to report frequency changes in the middle tone of the pattern. Three experimental conditions were formed: constant, random, and structured. In the constant condition observers listened to a single pattern. The observers in the structured and random conditions listened to 12 patterns, but the tonal patterns in the structured condition were arranged to reflect structural rules. Musical training made no difference, but magnitude of the frequency change was highly significant in discrimination performance. A non-parametric statistical analysis revealed a significant effect among the three conditions. It was demonstrated that a structured pattern of tones provided a knowledge source from which observers could effectively abstract information for frequency discrimination judgements. (Author)