Neural Correlates of Goal-directed Action Observation and Execution in Children With Unilateral Cerebral Palsy

Cerebral palsy (CP) is the most common childhood-onset motor disorder, with Unilateral Cerebral Palsy (UCP)- motor impairment predominantly impacting one side of the body-representing the most frequent form of CP. Among available rehabilitation programs, Action Observation Treatment (AOT) has gained increasing attention for its demonstrated effectiveness in improving manual motor function. AOT involves the systematic observation of goal-directed actions followed by their execution/imitation and is thought to leverage the mirror mechanism and its role in motor learning. Specifically, it relies on the neurophysiological principle that observing others' actions activates the same neural structures involved in executing those actions, reflecting the engagement of the mirror neuron system (MNS). In children with CP, the feasibility and effectiveness of AOT have been shown functionally (Sgandurra et al., 2013, Buchignani et al., 2019). However, despite its theoretical grounding in MNS functioning, the neurophysiological correlates of this system in children with CP remain less characterized, with only limited investigations using functional neuroimaging (e.g., Sgandurra et al., 2020) or neurophysiological methods such as electroencephalography (EEG; e.g., Demas et al., 2019). This observational study aims to characterize the neurophysiological signatures of action execution and action observation in children aged 5-15 years with a diagnosis of UCP compared to a group of age-matched typically developing (TD) peers. To this end, non-invasive high-density EEG (hdEEG) will be used to quantify sensorimotor cortex modulation through mu-rhythm reactivity-specifically event-related desynchronization (ERD) and synchronization (ERS)-and its topographical distribution during an active visuo-motor task involving upper limbs. Mu-rhythm desynchronization (or suppression) over sensorimotor regions is a well-established marker of MNS engagement. A secondary objective is to examine the r