Abstract:
This study aimed at determining the effect of cathodal Transcranial Direct-Current Stimulation (c-tDCS) of Dorsolateral Prefrontal Cortex (DLPFC) on learning simple volleyball serves. This semi-experimental study was performed as pre-test and post-test with a control group. Thirty male volleyball players with an average age of 14±0. 50 years were selected through purposeful sampling based on inclusion and exclusion criteria. The participants were randomly assigned to experimental (n=15) and control (n=15) groups. During eight consecutive sessions, the left DLPFC of participants was stimulated for 10 min using sham and real c-tDCS of 1. 5 mA before each session. The participants then performed 35 simple volleyball serves. Absolute error and total variability of participants' performance in pre-test, in the first, third and eighth sessions were recorded. Data analysis by repeated-measures showed that there was a significant difference between absolute error (F=14. 597, P = 0. 001) and total variability (F=17. 523, P = 0. 001) of experimental and control group performance. ANCOVA showed that absolute error and total variability of the experimental group performance was respectively (P = 0. 013 and P = 0. 018) in the first session, (P = 0. 021 and P = 0. 007) in the third session and (P = 0. 001 and P = 0. 001) in the eighth session, which were significantly higher than that in the control group. Thus, it seems that c-tDCS of DLPFC is associated with reduced declarative memory activity in the cognitive stage leading to a negative impact on serve learning in beginner volleyball learners.
Machine summary:
The Effect of Cathodal Transcranial Direct-Current Stimulation (c-tDCS) of Dorsolateral Prefrontal Cortex (DLPFC) on Learning Simple Serves in Beginner Volleyball Learners Seyed Kazem Mousavi Sadati, Ph. D.
Sc. Department of Physical Education & Sport Sciences, East Tehran Branch, Islamic Azad University, Tehran, Iran Abstract This study aimed at determining the effect of cathodal Transcranial Direct-Current Stimulation (c-tDCS) of Dorsolateral Prefrontal Cortex (DLPFC) on learning simple volleyball serves.
Based on the concepts of explicit and explicit learning, the first hypothesis can be put forward in this way that: Any intervention reducing activation of the left DLPFC may prevent the use of verbal working memory and improve motor learning, especially those who are in association and Autonomous phase (McKinley, McIntire, Nelson & Goodyear, 2017).
Based on Fitts and Posner's model (1967), the second hypothesis can be put forward that: In beginners who are in the cognitive stage, any intervention inhibiting left DLPFC activation may prevent the use of working memory, reduce verbal analytical (declarative memory) processes involvement in motor control and decrease motor learning, especially in beginners.
For this reason, one, three and eight sessions of DLPFC electric stimulation in the beginner participants of this study during how-to-serve learning sessions resulted in impaired working memory learning, reduced explicit verbal analysis in motor control -which improves apparent learning in the cognitive phase - and decreased absolute and total error of the experimental group as compared to the control group.