Measures of extents of laterality for high-frequency "transposed" stimuli under conditions of binaural interference.
Our purpose in this study was to determine whether across-frequency binaural interference would occur if ITD-based extents of laterality were measured using high-frequency transposed stimuli as targets. The results of an earlier study [L. R. Bernstein and C. Trahiotis, J. Acoust. Soc. Am. 116, 3062-3069 (2004)], which focused on threshold-ITDs, rather than extents of laterality, suggested that high-frequency transposed stimuli might be "immune" to binaural interference effects resulting from the addition of a spectrally remote, low-frequency interferer. In contrast to the earlier findings, the data from this study indicate that high-frequency transposed targets are susceptible to binaural interference. Nevertheless, high-frequency transposed targets, even when presented along with an interferer, yielded greater extents of ITD-based laterality than did high-frequency Gaussian noise targets presented in isolation. That is, the "enhanced potency" of ITDs conveyed by transposed stimuli persisted, even in the presence of a low-frequency interferer. Predictions made using an extension of the model of Heller and Trahiotis [L. M. Heller and C. Trahiotis, J. Acoust. Soc. Am. 99, 3632-3637 (1996)] accounted well for across-frequency binaural interference obtained with conventional Gaussian noise targets but, in all but one case, overpredicted the amounts of interference found with the transposed targets.
Bernstein
Leslie R
LR
Department of Neuroscience and Department of Surgery (Otolaryngology), University of Connecticut Health Center, Farmington, Connecticut 06030, USA.
Trahiotis
Constantine
C
D000161:Acoustic Stimulation / Q000295:instrumentation*; D000328:Adult; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009622:Noise / Q000009:adverse effects; D010470:Perceptual Masking / Q000502:physiology*; D010898:Pitch Perception / Q000502:physiology*; D013018:Sound Spectrography