Abstract:

Speech clarity judgments of bandpass filtered sentences were measured by category rating and paired comparisons in five age groups---4, 5, 6, 7, and 8 years old, and adults [data for children were provided from Eisenberg and Dirks, J. Speech Hearing Res. 38, 1157--1167 (1995)]. The judgment data within each age group were subjected to information theory and variance estimation analytical techniques in order to investigate developmental differences in task performance capability. All response variability was converted into equivalent signal detection ``error'' components, representing the ability of subjects in a given age group to perform a given psychophysical procedure. Preliminary results revealed a different developmental trend for each psychophysical procedure. For category rating, children 4 to 6 years of age exhibited higher error components in their responses, suggesting reduced capability to extract information compared with adults. In contrast, children as young as 5 years of age were approaching adultlike low error components in the paired comparisons. In this particular study, paired comparisons may provide a greater amount of information with less variance than category rating when subjective judgments of sound quality are measured. [Work supported by NIH.]