Factors accounting for performance in a frequency-sample-discrimination task with distracters

Abstract

This paper presents results of fitting several linear models, including the CoRE model of Lutfi [R. A. Lutfi and K. A. Doherty, J. Acoust. Soc. Am. 96, 3443–3450 (1994)] to data from a study of the interaction of target and distracter tones in a sample-discrimination task. In this 2IFC task, ten listeners judged which of two pairs of target tones were drawn from the higher of two overlapping frequency distributions. After training with targets alone, two distracter tones were presented simultaneously with the target tones, with each distracter placed in a frequency region remote from the target region. The important variables were the frequency regions and degree of frequency variability of targets versus distracters. Main features of the data included a large range of individual differences, a dominance of the effects of lower-frequency context tones over the higher-frequency context tones in many conditions, and differences in performance in the baseline, no-context conditions. When stimulus variability, perceptual weights across frequency, and performance in the no-context conditions are included as factors in the analysis, both mean and individual performance can be described reasonably well. [Work supported by NIDCD.]