Agnes Lukács, Budapest University of Technology and Economics, Department of Cognitive Science
Monday, May 23 2016, 11h Salle de réunion du LPP, H432, 4ème étage, Centre Biomédical des Saints Pères 45 rue des Sts Pères, 75006 Paris
Different forms of memory and learning in Specific Language Impairment
There is increasing evidence that different memory systems play important roles in Specific Language Impairment (SLI). The majority of research in SLI has focused on working memory, but there is increasing interest in long-term memory systems, in particular procedural and declarative memory. The aim of the talk is to present results from verbal and nonverbal long-term memory tasks examining 1) skill leaning (SL) and 2) declarative learning (DL) in children with SLI and their age-matched typically developing peers (TD). We tested skill learning using 1) the Serial Reaction Time Task (SRT) testing the learning of motor sequences and 2) an artificial Grammar Learning (AGL) task testing the extraction of regularities from auditory sequences. We tested 29 children with SLI (mean age 9.1, SD: 1.28) and compared their performance to normative data from a larger group of typically developing (TD) children from their age-group. For the two sequence learning tasks, a significantly smaller proportion of children showed evidence of learning in the SLI than in the TD group (2-tests, p < 0.001 for the SRT task, p < 0.05 for the AGL task), while the proportion of learners on the WP task was the same in the two groups. The level of learning for SLI learners was comparable to that of TD children on all tasks (with great individual variation). Declarative memory was tested by examining recognition memory after incidental encoding with both verbal and non-verbal stimuli in identical tasks, 10 minutes after encoding, but also 1 day later, to test for consolidation effects. Our results suggest that in the visual domain, declarative memory is a strength in SLI: in the Retention phases, children with SLI show the same level of performance as TD children. In the verbal task, the overall performance of the TD group was significantly better than that of the SLI group. Taken together, these findings show that while domain-general processes of sequence learning tend to be vulnerable in SLI, declarative memory as a strength can play an important compensatory role.