The Impact of Dual-Tasking on Verbal Short-Term Memory in Children with Specific Language Impairment

Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances decreased to a larger extent in children with SLI as compared to their unaffected peers when the processing demands of the task increased (e.g., Ellis Weismer, et al., 2005; Montgomery, 2000a,b). However, in these studies, the increase in attention processing demands went with an increase in linguistic processing demands. Since children with SLI experience language processing problems, it is not clear whether general attention problems or language processing problems are at the root of their larger performance decrease as compared to their unaffected peers.
This study aims at directly assessing the hypothesis that limitations in general attentional capacity are at the root of poor STM performances in children with SLI, using an attention demanding visual search task administered concurrently with nonword repetition task.
Twenty-three children with SLI, 23 age-matched children, and 23 nonword span-matched children performed immediate serial recall tasks of nonwords. The STM lists were presented either alone or concurrently with the target detection task. Moreover, the target detection task either stopped or continued when children had to recall the nonwords.
Results show a main effect of dual task condition on both nonword repetition accuracy and target detection accuracy. Performances in children with SLI were not more affected than in controls by the necessity to perform a concurrent visual attention task during nonword lists presentation. However, nonword recall seemed to be more challenging for children with SLI than for age-matched controls. Indeed, performances in the visual task were lower in children with SLI than in their age-matched controls, but not as compared to nonword span-matched controls.