Speech perception and lexical effects in specific language impairment

Abstract

Using an identification task, we examined lexical effects on the perception of vowel duration as a cue to final consonant voicing in 12 children with specific language impairment (SLI) and 13 age-matched (6;6–9;6) peers with typical language development (TLD). Naturally recorded CV/t/sets [word–word (WW), nonword–nonword (NN), word–nonword (WN) and nonword–word (NW)] were edited to create four 12-step continua. Both groups used duration as an identification cue but it was a weaker cue for children with SLI. For NN, WN and NW continua, children with SLI demonstrated certainty at shorter vowel durations than their TLD peers. Except for the WN continuum, children with SLI demonstrated category boundaries at shorter vowel durations. Both groups exhibited lexical effects, but they were stronger in the SLI group. Performance on the WW continuum indicated adequate perception of fine-grained duration differences. Strong lexical effects indicated reliance on familiar words in speech perception.

Keywords:

• specific language impairment
• speech perception
• lexicon
• categorical perception

Acknowledgment

Lawrence J. Raphael, PhD provided valuable input and assistance in the design of the stimuli and the experiment.

Declaration of Interest: This work was supported by grants RO1DC003885, 1RO1DC011041, and P50 DC00223 (Project 4) from the NIDCD and by a PSC-CUNY Research Grant to the first author. The research was conducted at the Albert Einstein College of Medicine and was included in a dissertation by the second author, under the direction of the first author, at the Graduate Center of the City University of New York. The authors have no conflict of interest.