Shifting in School-Aged Children With Developmental Language Disorder.

Purpose: Many children with developmental language disorder (DLD) demonstrate impaired executive function skills, including shifting. However, language demands in shifting tasks make it difficult to accurately assess shifting ability. Combining behavioral measures (accuracy, reaction time) with event-related potentials (ERPs) can help dissociate the effects of language and shifting ability on task performance.

Method: This study examined shifting in 40 children, aged 8-12 years (20 with DLD, 20 with typical language development [TD]). A cued set-shifting paradigm presented visual cues to switch between two response rules. Single-rule blocks contained "Single" trials that repeated the same rule. Mixed-rule blocks contained "Switch" and "Stay" trials that alternated rules pseudorandomly. The amplitude and latency of the cue-P3 ERP component, indexing shift cue processing, were compared across groups and trial types.

Results: Children with DLD had significantly longer reaction times than children with TD, but they achieved comparable accuracy. Mixing Cost was significantly greater for children with TD than DLD, reflecting an appropriate response to increased task difficulty in the mixed-rule blocks compared to the single-rule blocks. Switching Cost was significantly greater for children with DLD than TD, suggesting protracted processing of Switch versus Stay trials in the mixed-rule blocks. ERP data revealed different patterns of the cue-P3 component in each group; however, differences were not statistically significant. Children with TD had similar amplitude and latency across trial types. Children with DLD exhibited reduced amplitude for Single cues and delayed processing of Switch cues. Correlations between behavioral and electrophysiological measures were limited.

Conclusions: While children with DLD performed as accurately as their peers with TD, they took significantly longer to process cues and submit responses. Electrophysiological data suggest that cue processing may differ among children with DLD compared to those with TD, but more work is needed to assess the nature of these differences.