ASA 125th Meeting Ottawa 1993 May

3aSP14. Processing of stop-vowel syllables by normal and language-impaired children.

Rachel E. Stark

Audiol. and Speech Sci., Purdue Univ., West Lafayette, IN 47907

John M. Heinz

Kennedy--Krieger Inst., Baltimore, MD 21205

It has been claimed that language-learning disordered children have impaired rapid-rate auditory processing. One manifestation is the failure to identify stop-vowel syllables; another less fine-grained discrimination of stop-vowel syllables. In the present study, 20 language-impaired (LI) and 20 normal (LN) children (6 to 10 years) attempted to identify /ba/--/da/ syllables within an adaptive paradigm. When they failed to do so, they were given a change/no change discrimination task with these stimuli. Formant transition duration (FTD) ranged from 80 to 40 ms. The syllable pairs had either five or two formants. As in previous studies, LI children failed the identification task, even for syllables of 80-ms FTD, significantly more often than LN. They were able to discriminate the syllables. Number of formants was not a significant variable. A subgroup of LI and LN children were subsequently asked to produce the test syllables. In both groups, children unable to produce the syllables had difficulty in identify them. The reverse was not true. Perception difficulties were not predictive of production errors. [Work supported by NIH.]