Effective Somatosensory and Cross-Modal Evaluation in Children with Hemiparesis and Neurotypically developing Children using MSI Caterpillar*

Motor function and tactile perception are deeply interconnected. Individuals with paresis serve as an example of this intricate interplay between motor and tactile systems, by showing that motor recovery depends on improvement in the somatosensory function. In the clinical practice, somatosensory assessment tends to be neglected, or, when conducted, faces challenges due to a lack of consistency in methodology, which might also impact the development of effective rehabilitation strategies. Somatosensory and cross-modal perception in children with hemiparesis is particularly underexplored. With this work, using a new version of the MSI Caterpillar, our goal was (1) to contribute to the understanding of somatosensory perception in children with hemiparesis, (2) investigate how cross-modal inter-actions can influence their perceptions, and (3) bridge the gap between theoretical research and practical application, offering new pathways for technological integration in clinical settings. By measuring the reaction times (RTs) in the detection of a tactile signal and the localization of tactile, audio-tactile and visual-tactile stimuli, we effectively detect somatosensory impairments in the more affected arm of children with hemiparesis compared to the non-dominant one of typically developing peers, suggest the presence of cross-modal interactions, and highlight the dominant role of vision in space location. In addition, our data revealed that attraction towards the wrist in the localization of tactile stimuli is a developmental milestone impaired in hemiparesis.