[Multiple-scale intermuscular coupling network analysis].

Area of Science:

• Biomechanics and Motor Control
• Complex Network Analysis
• Signal Processing

Background:

• Understanding intermuscular coupling is crucial for analyzing motor control and coordination.
• Existing methods may not fully capture the multi-scale temporal and spatial dynamics of muscle interactions.
• Complex network theory offers a framework for analyzing intricate relationships within biological systems.

Purpose of the Study:

• To propose and validate a new multi-scale intermuscular coupling network analysis method.
• To investigate the time-frequency scale characteristics of intermuscular coupling during reaching exercises in healthy subjects.
• To quantitatively describe multi-scale intermuscular coupling strength using network parameters.

Main Methods:

• Development of a novel MVMD-Copula MI method combining multivariate variational modal decomposition (MVMD) and Copula mutual information (Copula MI).
• Construction of an intermuscular coupling network model based on the MVMD-Copula MI approach.
• Analysis of upper limb muscle coupling during reaching exercise using network parameters like node strength and clustering coefficient across six time-frequency scales.

Main Results:

• Significant differences in intermuscular coupling characteristics were observed across the six time-frequency scales.
• The triceps brachii (TB) exhibited high coupling strength with the middle deltoid (MD) and posterior deltoid (PD), indicating close functional connections.
• The biceps brachii (BB) demonstrated independence from other analyzed muscles, suggesting distinct functional roles.

Conclusions:

• The proposed MVMD-Copula MI method effectively quantifies multi-scale intermuscular coupling strength.
• Intermuscular coupling networks exhibit scale-dependent characteristics during reaching movements.
• This approach holds significant promise for advancing the understanding of complex muscle coordination in motor tasks.