The theoretical assumption guiding this project is that inhibition control and working memory are distinguishable but closely related functions (Friedman & Miyake, 2004). There is evidence for deficits in working memory in children with specific language impairment (SLI), but there are barely any investigations of possible links between working memory and inhibition control in this population. The long-term goal of this project is understanding the relations between the various inhibition functions (inhibition of a prepotent response and resistance to interference) and working memory in children with SLI.
The specific aims of the project are 1. to test the """"""""inefficient inhibition hypothesis"""""""" (Wilson & Kipp, 1998); 2. to examine the effects of contextual manipulations on inhibition control; 3. to investigate whether inhibition control in children with SLI is similar across domains (verbal and non-verbal); 4. to study developmental changes in inhibition and in resistance to interference in school-age children with typical language development (TLD) and SLI; 5. to test the theory that there is """"""""no distinction between the processes underlying typical and atypical executive functions"""""""" (Roberts & Pennington, 1996). Three groups of school-age children (SLI, age-matched, language-matched controls; total n=90) will participate in this study. The proposed information processing paradigm is a novel computerized task that will enable us to examine the effects of contextual manipulations on inhibition control and on working memory within a unitary experimental setting. We hypothesize that the various inhibition functions play a crucial role in working memory performance and that data from contextual manipulations will reveal critical relations between inhibition and the working memory deficit in this population. The expected outcome is that children with SLI are inefficient inhibitors and that a detailed qualitative analysis including error data and a description of children's strategies will reveal specific underlying patterns behind SLI children's atypical performance in inhibition control and working memory. These hypotheses stem from our earlier results that showed a deficit in simultaneous processing and in suppressing irrelevant information in children with SLI. Thus, we expect that children with SLI will exhibit performance characteristics that differ markedly from that of children with TLD. If the results confirm our hypotheses, the findings will have important theoretical and clinical implications regarding the impact of inhibition control on performance in multitasks, such as language/reading comprehension and following complex instructions. The proposed study will investigate the relations between inhibition control (inhibition of a prepotent response & resistance to interference) and working memory in children with language impairment (SLI). There is evidence for working memory deficits in children with SLI, but there are barely any investigations of possible links between working memory and inhibition control in this population. Inhibition control may underlie many of those difficulties that children with SLI experience in everyday learning situations. ? ? ?
