Abstract
Muscle weakness is a major issue. An increased intracortical inhibition and a lack in central motor drive have been recently reported in COPD (Alexandre et al., PLoS ONE 9:e100961, 2014). Therefore the aim of this study was to investigate the possibility to counterbalance this phenomenon by using non-invasive cortical neuromodulation.
Ten COPD (GOLD II-IV) and nine matched control subjects were randomly assigned to undergo 10min/2mA anodal (intervention) or sham high-definition transcranial direct-current stimulation (HD-tDCS) of the dominant primary motor cortex (M1) in a double-blind design with at least 72h between each session. Strength of the vastus lateralis (VL), neuromuscular properties, motor potentials (MEP) and cortical silent period (CSP) evoked by transcranial magnetic stimulation from the dominant M1 towards the contralateral VL were measured before and after neuromodulatory intervention.
The intervention by anodal HD-tDCS resulted in decreased CSP (intracortical inhibition) while no difference was present in the control group (see Figure). However, strength and MEP (cortical excitability) were not affected by the neuromodulatory intervention.
This study showed that COPD patients exhibited reversible increased intracortical inhibition. These preliminary results are a step towards a better understanding of the pathophysiology of cortical disorders in muscle weakness in COPD patients.
- Copyright ©the authors 2017