Haskins Publications

Number	408
Year	1983
Drawer	7
Entry Date	11/19/1999
Authors	Repp, B. H., Milburn, C., & Ashkenas, J.
Contact
Publication	Perception & Psychophysics, 33, 333-337.
url	http://www.haskins.yale.edu/Reprints/HL0408.pdf
Abstract	Duplex perception--the simultaneous perception of a speech syllable and of a nonspeech chirp--occurs when a single formant transition and the remainder (the base) of a synthetic syllable are presented to different ears. Two experiments were conducted with 12 adults to test whether the speech percept derives from the dichotic fusion of the transition with the base or from phonetic information extracted directly from the isolated transition. In Experiment I, chirps and bases were presented to different ears, and Ss were asked to identify the consonant sounds. Results show that Subjects were unable to assign speech labels to isolated transitions in a consistent manner, although the same transitions led to accurate identification when paired with the constant base in the other ear. Experiment II used an AXB paradigm to show that selective attention to the ear receiving the base does not prevent the contribution of the contralateral transition to the speech percept. Both experiments support the hypothesis that the speech percept in the duplex situation results from dichotic fusion at a relatively early stage in processing.
Notes