Links Between Rhythmic Handwriting Deficits and General Rhythmic Abilities in Children With Developmental Coordination Disorder: a Pilot Study. TDC-Rythme

Patients with Developmental Coordination Disorder (DCD), a neurodevelopmental disorder that affects motor skills and motor learning (APA, 2013), have been reported to manifest rhythmic deficits in handwriting domain, as well as general rhythmic deficits (i.e., regardless handwriting context per se) (Rosenblum & Regev, 2013). Accordingly, children with DCD struggle in tasks like synchronising to an external musical rhythm (in rhythm production tasks) or even in discrimination tasks such as detecting beat deviations, i.e., in rhythm perception tasks (INSERM collective expertise, 2019).

These rhythmic deficits which manifest in a variety of tasks and conditions support the hypothesis of a "generalised dysrhythmia" in DCD, according to which the rhythmic deficits - in perceptual tasks and motor production - could have a common source, namely a mechanism devoted to rhythm processing (a cerebral mechanism involved in the perception of rhythm) and independent of the effectors involved and the type of task considered.

However, the nature of the relationships between general rhythmic skills (perceptual and motor) and rhythmic abilities when engaged in handwriting movement is largely unknown in DCD. Whether a common source drives these diverse rhythmic deficits remains to explore. If this hypothesis were to be confirmed, this would pave the way for innovative therapeutic tools (e.g., serious games) for training a central rhythmic processing mechanism (rhythm perception), which could positively impact in turn rhythmicity of thandwriting movement in this population.