What this Trial Is About

The complex and unclear relationship between language and executive function (EF) creates barriers to developing effective interventions for children with developmental language disorder (DLD) whose language difficulties often co-occur with impaired EF. Children and adults with typical language development (TD) facilitate their EF by using self-directed language, or verbal mediation, to guide conscious reflection and override habitual behaviors. Conversely, children with DLD do not use verbal mediation to support EF efficiently or effectively. Promising evidence suggests that language-based training can shape verbal mediation and improve EF task performance in children with TD, which makes it pertinent to determine whether verbal mediation training benefits children with DLD. Specifically, modeling interventions have been shown to promote learning of language forms without taxing the cognitive resources required for learning such as attention or working memory, which are known to be impaired among children with DLD. The long-term goal of the proposed work is to optimize intervention outcomes for children with DLD by elucidating the complex relationship between language and executive functions. The objective of this project is to determine the impact of modeling verbal mediation on shifting task performance in school-aged children with DLD. Shifting, also known as cognitive flexibility, is the ability to alternate between operations or mental sets. It is an important EF because it is the pivot point between multiple goal-directed tasks when language use is critical for guiding action. Children aged 8-10 years will complete three versions of a shifting task over three phases: pre-intervention, intervention, and post-intervention. During the intervention phase, half of the participants with DLD will be exposed to a task model with verbal mediation (training), while the other half will be exposed to a silent task model (control). The investigators will determine the effect of modeling verbal mediation on the subsequent use of verbal mediation (Aim 1) and behavioral and electrophysiological measures of shifting ability (Aim 2). Indirect measures of shifting (i.e., accuracy and reaction time) will be supplemented with an electrophysiological marker of shifting that reflects real-time cue processing. This combination of methods provides insight to changes in processing following intervention that may precede and predict subsequent changes in behaviors. Our central hypothesis is that modeling verbal mediation will facilitate more effective use of verbal mediation and improve shift cue processing in children with DLD. The project will provide a theoretical framework for the role of language in shaping goal-directed behavior and the first examination of electrophysiological change in shifting following a verbal mediation intervention. Results will have a significant impact on clinical practice by advancing knowledge about a promising language-based intervention to support EF and other goal-directed tasks.

Training Inner Speech in Children With Developmental Language Disorder