Effects of anodal tDCS on Motor Cortex to improve fine motor Skills /
Ahmad Maaz Ali
- 102p. Soft Copy 30cm
This investigation examined the efficacy of anodal transcranial direct current stimulation (tDCS) targeting the motor cortex for enhancing fine motor skill acquisition. Twenty healthy participants were randomly divided into two equivalent groups: an Active tDCS experimental cohort (n=10) and a Sham control cohort (n=10). The study implemented a comprehensive six-day experimental protocol to systematically assess tDCS effects on both behavioral motor performance and neurophysiological activity patterns. The experimental framework commenced with Day 1 baseline evaluations, during which all subjects completed initial electroencephalographic (EEG) recordings while performing a standardized training regimen. This regimen incorporated two validated assessments from the Fundamentals of Laparoscopic Surgery (FLS) evaluation suite: a bimanual peg transfer exercise and a unimanual bead placement task. These particular tasks were chosen based on their proven reliability for measuring fine motor coordination capabilities and manual precision. Throughout the intervention period (Days 2-4), both cohorts completed three daily training sessions, with the experimental group receiving active tDCS while the control group received sham stimulation. The stimulation protocol was administered concurrently with task performance to investigate potential motor learning facilitation effects. Post-intervention evaluations were conducted on Day 5, incorporating EEG recordings during task execution to capture immediate neuroplastic adaptations and assess short-term motor skill enhancements. To evaluate the persistence of observed improvements, a retention assessment was performed on Day 12, occurring one week following the final stimulation session. This follow-up evaluation required participants to repeat the identical FLS tasks while undergoing EEG monitoring to quantify sustained motor skill improvements. The results demonstrated statistically significant fine motor skill enhancement in the Active tDCS group compared to the Sham control group. The bimanual peg transfer task showed significant improvement (p = 0.0006), while the unimanual beads placement task demonstrated highly significant enhancement (p < 0.00000001). Motor skill retention remained statistically significant at the one-week follow-up assessment (p = 0.0021). XX Neurophysiological analysis revealed significant changes in EEG frequency bands, particularly within the beta frequency range, which showed a significant group × day interaction (p = 0.0444), indicating that tDCS produced greater changes in motor-related neural activity compared to sham stimulation. Alpha and gamma frequency bands exhibited trends toward statistical significance, though these did not reach conventional significance thresholds. Event-related desynchronization/synchronization (ERD/ERS) analysis demonstrated that the Active group exhibited increased ERD following intervention, reflecting greater cortical engagement, and elevated ERS at follow-up assessment, suggesting enhanced neural efficiency. Motor cortex electrodes (C3 and C4) in the Active group displayed greater ERD, indicating increased engagement of motor cortical regions during task performance. This investigation provides robust statistical evidence supporting tDCS as an effective intervention for enhancing motor cortex excitability and facilitating fine motor skill development. The findings demonstrate significant clinical relevance for applications in neurorehabilitation protocols, surgical skill training programs, and cognitive-motor therapeutic interventions. Future research directions may investigate varying stimulation parameters and diverse task configurations to further optimize tDCS efficacy for motor skill enhancement applications.