Multisession anodal transcranial direct current stimulation induces motor cortex plasticity enhancement and motor learning generalization in an aging population.
Clin Neurophysiol. 2017 Nov 21;:
Authors: Dumel G, Bourassa MÈ, Charlebois-Plante C, Desjardins M, Doyon J, Saint-Amour D, De Beaumont L
OBJECTIVES: The present aging study investigated the impact of a multisession anodal-tDCS protocol applied over the primary motor cortex (M1) during motor sequence learning on generalization of motor learning and plasticity-dependent measures of cortical excitability.
METHODS: A total of 32 cognitively-intact aging participants performed five consecutive daily 20-min sessions of the serial-reaction time task (SRTT) concomitant with either anodal (n = 16) or sham (n = 16) tDCS over M1. Before and after the intervention, all participants performed the Purdue Pegboard Test (PPT) and Transcranial Magnetic Stimulation (TMS) measures of cortical excitability were collected.
RESULTS: Relative to sham, participants assigned to the anodal-tDCS intervention revealed significantly greater performance gains on both the trained SRTT and the untrained PPT as well as a greater disinhibition of long-interval cortical inhibition (LICI). Generalization effects of anodal-tDCS significantly correlated with LICI disinhibition.
CONCLUSION: Anodal-tDCS facilitates motor learning generalisation in an aging population through intracortical disinhibition effects.
SIGNIFICANCE: The current findings demonstrate the potential clinical utility of a multisession anodal-tDCS over M1 protocol as an adjuvant to motor training in alleviating age-associated motor function decline. This study also reveals the pertinence of implementing brain stimulation techniques to modulate age-associated intracortical inhibition changes in order to facilitate motor function gains.
PMID: 29223355 [PubMed – as supplied by publisher]