Abstract:
The extent to which judgments of the laterality of SAM high-frequency carriers is influenced by other SAM tones was assessed in a stimulus-classification paradigm. The target was either a 4- or a 2-kHz tone modulated at 200 Hz, and the distractor was a 2- or 4-kHz tone modulated at rates ranging from 50 to 400 Hz. Of particular interest is the manner in which the weight given to the target is dependent upon the carrier and modulation frequencies. On each trial, the target was presented with one of ten envelope delays, as was the distractor. Each test interval was preceded by a diotic presentation of the target alone. The relative contributions of the envelope delays of the target and the distractor were assessed by the point-biserial correlations between the target/distractor delays and the type of response elicited (``left''/``right''). Although substantial individual differences were found in terms of which carrier was more potent and in how target weight depended upon modulation frequency, the relationship between target weight and modulation frequency tended to be the same for the two carrier frequencies for a given listener.