Anodal Transcranial Direct Current Stimulation (tDCS) Over the Primary Motor Cortex (M1) Enhances Motor Response Inhibition and Visual Recognition Memory.

BACKGROUND Transcranial direct current stimulation (tDCS) is a non-invasive brain modulatory technique that can boost cognitive processes and alter performance in cognitive tasks. The effect of anodal-tDCS on cognitive functions following a single session has been repeatedly reported. However, results are varied, mixed, and confounded by several factors, including differences in tDCS current intensity and sham conditions used. Therefore, we assessed the effect of a single session of anodal-tDCS over the primary motor cortex (M1) on cognitive functions, particularly response inhibitory control and visual recognition memory, in healthy adults. MATERIAL AND METHODS Thirty healthy male subjects participated in a randomized, double-blind, sham-controlled tDCS study (2 mA, for 20 min). In the sham stimulation, subjects received the same intensity (2 mA, for 30 s, ramped up, then ramped down). We assessed the cognitive functions response inhibitory control and visual recognition memory using the stop signal task (SST) and pattern recognition memory (PRM) task before and after the stimulation. RESULTS There was a statistically significant difference in cognitive function as assessed by the stop signal task go trial (SST) (P=0.019) and SST correct response time on go trials (P=0.04) after real stimulation only. There was no significant effect observed in sham condition. CONCLUSIONS The findings suggest that anodal-tDCS applied over M1 improves inhibitory control and visual recognition memory compared to sham stimulation. Thus, application of anodal-tDCS to the M1, as an integral node in inhibitory motor control, might be a promising adjuvant therapeutic intervention for modulation of motor response inhibition.

Prevalence of knee injuries among male college students in Riyadh, Kingdom of Saudi Arabia.

BACKGROUND: The knee is considered the most common injured joint between young sport participants. However, there is lack of proper prevalence estimation in our population. The purpose of this study was to identify the prevalence of knee injuries among male college students and to observe the demographic data associated with it. Our secondary objective was to evaluate the awareness and knowledge about these injuries. METHODS: This is a cross-sectional study. A survey was distributed to collect the data among male college students, King Saud University, Riyadh, Saudi Arabia. Out of 688 students who participated and completed the questionnaire, a total of 482 were considered valid and met the inclusion criteria. Data were analyzed using Statistical Package for Social Sciences (SPSS). RESULTS: The overall prevalence of knee injury was 23.2% (n = 112). Most of them injured during sport activities especially soccer and 68.7% involved in a non-contact mechanism of injury. Among those who went to a hospital mostly were diagnosed as contusion (31.4%) then as meniscus tear, ACL, and collateral ligament injury, respectively. Majority was treated conservatively and only 10.7% needed surgery surprisingly. There was no statistically significant difference between those who are injured and whether they were warmed up and stretched or not (P = 0.619). Low level of knowledge about knee injuries was noticed among the participants 57.7%. CONCLUSION: Our study has highlighted the high prevalence of knee injuries and the need to raise the level of awareness and knowledge about these injuries in our population. Soccer was the most common sport associated with knee injuries; most of these injuries were treated conservatively.