PROJECT SUMMARY Developmental language disorder (DLD) is a highly prevalent impairment in the use and understanding of spoken and written language that contributes to poor academic outcomes and social-emotional distress. Research suggests that executive function, a set of skills responsible for controlling and monitoring cognitive resources, is also impaired in children with DLD. However, executive function task performance is often facilitated by verbal mediation, or the use of language through internal self-talk to guide behavior. Given evidence that verbal mediation is limited in children with DLD, it is difficult to discern whether poor performance on executive function tasks is due to ineffective verbal mediation, weak executive function, or both. The presence of co-occurring deficits can obscure assessment results and lead to the implementation of ineffective interventions. The long- term goal of this work is to improve assessment and intervention for children with DLD by addressing the critical gap in knowledge about the relations between language and executive function skills. The objective of this project is to dissociate the effects of verbal mediation and executive function on a shifting task in school-aged children with DLD and typical development (TD). Shifting is the ability to alternate between operations or mental sets, and it is critical for planning and problem solving in an academic environment. Aim #1 will examine the effect of verbal mediation on shifting task performance using behavioral measures of switch cost, or the slowing of response following a shift cue, under conditions that allow or prevent the use of verbal mediation. We hypothesize that when verbal mediation is prevented, switch costs will increase for children with TD and stay the same or decrease for children with DLD. This pattern would indicate that ineffective verbal mediation is contributing to poor shifting task performance in children with DLD. Aim #2 will isolate the effect of executive function on shifting task performance using temporally sensitive event-related potentials (ERPs) extracted from electroencephalography (EEG) recorded from the scalp. The project will capitalize on a well-studied ERP marker of shift detection, the cue-P3. We predict that children with DLD will show increased activation of the executive system reflected in an equally large brain response (i.e., large amplitude of the cue-P3) when shifting is needed and when it is not. This pattern would be consistent with previous findings in individuals with a weak executive control system. The proposed project will provide the PI with training in using EEG methodology, analyzing ERP data, establishing a productive and independent line of research, and improving grantsmanship and leadership skills. The proposed research and training activities will take place in an exceptional scientific environment with a highly accomplished mentorship team. Findings from the proposed work will have a posi...