Abstract:
Skill implies a certain level of expertise when performing a voluntary movement. Research has identified that skilled movement is characterized by decreased cortical activation in the motor cortex and decreased coherence between neuronal populations. In a subset of the population, over-training can lead to the degradation of motor pathways of a specific skilled movement. Focal task specific dystonia, a movement disorder characterized by abnormal muscle contractions, can develop in people who are highly skilled at certain movements (musicians, athletes). Dystonic symptoms emerge when these patients are performing their well-learned movements. Previous EEG work has identified certain EEG signatures which are abnormal in dystonia. In this study, we investigated if similar beta frequency signatures and response patterns may be present in healthy people while performing familiar (‘skilled’) movements. We found that there is a significantly weaker beta power driven by post-movement beta rebound in ‘skilled’ trials compared to ‘unskilled’ trials, but no difference in pre-movement beta desynchronization or beta power during movement. Additionally, there is greater variability in response times during ‘unskilled’ trials, but no significant difference in incorrect responses. Our findings contribute to the field of skill-related research by examining ‘skilled’ conditions performed in healthy people as over-trained movements with the potential connection to focal task specific dystonia. Thus, our study suggests the need for further investigation in this relationship between skill-related and task-specific dystonic research.