ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

2pPP4. The relationship between binaural fusion and binaural interference.

Raymond H. Dye, Jr.

Parmly Hearing Inst., Loyola Univ., 6525 N. Sheridan Rd., Chicago, IL 60626

A stimulus-classification paradigm was used to examine the extent to which judgments of the laterality of 753-Hz targets were influenced by distractors of different frequency. On each trial, the target was presented with one of ten different interaural differences as was the distractor. Each test interval was preceded by a diotic presentation of the target alone. During a block of 100 trials, each combination of target-distractor interaural differences was presented once. The relative weights given to the target and the distractor were assessed by the slope of the best linear boundary between left and right responses. Data were collected for conditions in which the cues were interaural differences of level or time. For all conditions for which target and distractor weights were obtained, binaural interference was measured by determining threshold interaural differences for conditions in which the target was presented alone and in the presence of a diotic distractor. For most subjects, greater interference was obtained when the distractor was at a frequency that was given great weight, although the frequencies weighted most heavily for interaural differences of time were not the same as those weighted heavily for interaural differences of level. [Work supported by NIH.]