Cervical Electrical Neuromodulation Effectively Enhances Hand Motor Output in Healthy Subjects by Engaging a...

Area of Science:

• Neuroscience
• Motor Control
• Rehabilitation

Background:

• Transcutaneous spinal cord stimulation, termed electrical enabling motor control (eEmc), offers a non-invasive method to modulate the sensory-motor system.
• Understanding the synergistic effects of eEmc and motor training on neural plasticity is crucial for optimizing rehabilitation strategies.

Purpose of the Study:

• To investigate whether combining eEmc with hand training enhances hand function in healthy subjects more than individual interventions.
• To explore the underlying spinal and cortical plastic changes induced by these interventions.

Main Methods:

• Ten healthy participants underwent three conditions: hand grip training alone, eEmc alone, and combined eEmc with hand training.
• Functional assessments included the Box and Blocks Test (BBT) and maximal voluntary contraction (MVC).
• Neurophysiological measures comprised spinal and cortical motor evoked potentials (sMEP, cMEP), resting motor threshold (RMT), short-interval intracortical inhibition (SICI), and F-wave analysis.

Main Results:

• The combination of eEmc and hand training maintained MVC, increased F-wave amplitude and persistence, reduced RMT, and facilitated cMEP amplitude.
• eEmc alone increased F-wave amplitude, while hand training alone decreased MVC and increased RMT and SICI.
• Combined intervention demonstrated superior effects on motor output and neural plasticity compared to individual interventions.

Conclusions:

• eEmc combined with hand grip training enhances hand motor output and induces beneficial plastic changes at both spinal and cortical levels in healthy individuals.
• This synergistic approach suggests that electrical neuromodulation primes neural networks for plasticity, with concurrent motor training driving functional improvements.