Purpose: According to the procedural deficit hypothesis (PDH), difficulties in the procedural learning (PL) system may contribute to the language difficulties observed in children with specific language impairment (SLI).
Method: Fifteen children with SLI and their typically developing (TD) peers were compared on visual PL tasks-specifically, deterministic serial reaction time (SRT) tasks. In the first experiment, children with SLI and their TD peers performed the classical SRT task using a keyboard as response mode. In the second experiment, they performed the same SRT task but gave their responses through a touchscreen (instead of a keyboard) to reduce the motor and cognitive demands of the task.
Results: Although in Experiment 1, children with SLI demonstrated learning, they were slower and made more errors than did their TD peers. Nevertheless, these relative weaknesses disappeared when the nature of the response mode changed ( Experiment 2).
Conclusions: In this study, the authors report that children with SLI may exhibit sequential learning. Moreover, the generally slower reaction times observed in previous deterministic SRT studies may be explained by the response mode used. Thus, our findings are not consistent with the predictions of the PDH, and these findings suggest that language impairments in SLI are not sustained by poor procedural learning abilities.