A longitudinal exploration of inhibitory control in children with Developmental Language Disorder

Previous research suggests that children with Developmental Language Disorder (DLD) exhibit weaker executive functioning, but there is limited understanding of how inhibitory control develops in this population over time. Adopting a longitudinal perspective, this study assessed inhibitory control in children with DLD compared with their typical developing peers.

We used a Flanker task to longitudinally assess interference control, a component of inhibitory control, in a group of 12 children with DLD and 31 typical development (TD) peers across three waves. At wave 1, participants had a mean age of 10.5 years, with data collected across three waves spanning ages 8.3 to 16.1 years.

Regarding Response Time, incongruent trials were significantly slower than congruent and neutral trials across all waves for both groups separately. Moreover, the DLD group showed a larger interference effect (IE) than TD peers, but only in the first wave. Concerning accuracy, the DLD group showed lower scores in the first wave compared to the TD group. However, these differences diminished in the last two waves. Finally, no differences were found between groups in IE accuracy.

The DLD group showed a poorer overall inhibition compared to the TD group; however, this deficit seems to vanish over time. Our hypotheses are partially confirmed, aligning with evidence of deficits in inhibitory control in children with DLD. This suggests a domain-specific difficulty with inhibitory control that ameliorates during adolescence in DLD, driven by longer response times during incongruent trials and higher interference effects.