No abstract

The association of mCIMT with brain stimulation improves clinical gains in rehabilitation after stroke. The improvement in motor recovery (assessed by Fugl-Meyer scale) was only observed after anodal tDCS. The modulation of damaged hemisphere demonstrated greater improvements than the modulation of unaffected hemispheres.

Mental practice can induce significant neural plasticity and result in motor performance improvement if associated with motor imagery tasks. Given the effects of transcranial direct current stimulation (tDCS) on neuroplasticity, the current study tested whether tDCS, using different electrode montages, can increase the neuroplastic effects of mental imagery on motor learning. Eighteen healthy right-handed adults underwent a randomised sham-controlled crossover experiment to receive mental training combined with either sham or active anodal tDCS of the right primary motor cortex (M1), right supplementary motor area, right premotor area, right cerebellum or left dorsolateral prefrontal cortex (DLPFC). Motor performance was assessed by a blinded rater using: non-dominant handwriting time and legibility, and mentally trained task at baseline (pre) and immediately after (post) mental practice combined with tDCS. Active tDCS significantly enhances the motor-imagery-induced improvement in motor function as compared with sham tDCS. There was a specific effect for the site of stimulation such that effects were only observed after M1 and DLPFC stimulation during mental practice. These findings provide new insights into motor imagery training and point out that two cortical targets (M1 and DLPFC) are significantly associated with the neuroplastic effects of mental imagery on motor learning. Further studies should explore a similar paradigm in patients with brain lesions.

Low or very low quality of evidence suggests that our primary outcome evaluation failed to find support for the superiority of NIBS over sham treatment. Although, subgroup analysis reveals that tDCS have moderate to high effects and could be a promising nonpharmacological alternative to pain control, mainly for painkiller intake reduction. However, there is a need for larger controlled trials with methodological rigor, which could increase the power of result inference.

The cerebellum plays an important role in the planning, initiation and stability of movements, as well as in postural control and balance. Modulation of neural regions underlying balance control may be a potential alternative to treat balance impairments in cerebellar patients. Transcranial direct current stimulation (tDCS) is a noninvasive and safe tool capable to modulate cerebellar activity. We aim to investigate the effects of cerebellar tDCS (ctDCS) on postural balance in healthy individuals. Fifteen healthy and right-handed subjects were submitted to three sessions of ctDCS (anodal, cathodal and sham), separated by at least 48 h. In each session, tests of static (right and left Athlete Single Leg tests) and dynamic balance (Limits of Stability test) were performed using the Biodex Balance System before and immediately after the ctDCS. The results revealed that cathodal ctDCS impaired static balance of healthy individuals, reflected in higher scores on overall stability index when compared to baseline for right (p = 0.034) and left (p = 0.01) Athlete Single Leg test. In addition, we found significant impairment for left Athlete Single Leg test in comparison to sham stimulation (p = 0.04). As far as we know, this is the first study that points changes on balance control after ctDCS in healthy individuals. This finding raises insights to further investigation about cerebellar modulation for neurological patients.