Abstract:

To compare the integration of acoustic information in phonetic perception by young children and adults, second formant frequency at voicing onset (F2 onset) and gap duration were varied as cues distinguishing ``spa'' and ``sa.'' Listeners performed same--different (AX) discrimination in four conditions. The gap of the standard (A) stimulus was always consistent with ``spa;'' gaps of the comparison (X) stimuli decreased in duration along a continuum, thus becoming more consistent with ``sa.'' In the two ``one-cue'' conditions, F2 onset was the same for the A and X stimuli. In the ``two-cue cooperating'' condition, F2 onset for stimulus A supported ``spa,'' and F2 onset for X stimuli supported ``sa.'' In the ``two-cue conflicting'' condition, F2 onset for stimulus A supported ``sa,'' and F2 onset for X stimuli supported ``spa.'' Results led to three conclusions: (1) Child and adult discrimination performance was similar overall, suggesting that the child-adult differences across conditions were not due to differences in general auditory ability. (2) The acoustic cues were integrated in phonetic perception, but acoustic differences were nonetheless accessible perceptually for AX discrimination. (3) However, these acoustic differences are less accessible to adults than to children after integration in phonetic perception. [Work supported by research Grant No. 5 RO1 DC 00633 from the NIDCD/NIH.]