Study on the Influence of Proprioceptive Control Versus Visual Control on Reaction Speed, Hand Coordination, and Lower Limb Balance in Young Students 14–15 Years Old

Currently, sports activities require a high reaction speed, coordination, and balance, highlighting the relationship between proprioceptive control, visual control, and hand–eye coordination in youth. The present research assessed the proprioceptive control, reaction speed, and lower limb balance of youth from five different schools to identify the level of physical preparation of children in this direction. This prospective study was conducted between 1 January, 2020, and 29 February, 2020. A total of 107 healthy children (33 females and 74 males) with appropriate medical conditions, aged between 14 and 15 years, from five Romanian schools were included in the experiment. All children were assessed for visual control and reaction speed with the ruler drop test, and for lower limb balance, the standing stork test was used. Statistical analysis included descriptive statistics, data series distribution, and comparison of means and medians using specific statistical programs. Comparison of medians highlighted significant statistical differences in the standing stork test with eyes closed and the dominant leg compared with the nondominant leg (p = 0.0057). Males were compared to females at the nondominant leg (p = 0.0179); closed eyes were compared with opened eyes for the nondominant leg (p = 0.0175 and 0.0006) for the ruler drop test comparing the dominant hand with the nondominant hand (p = 0.0212). Children who engage in sports activities better integrated sensory information in motor action execution based on reaction speed and coordination with the nondominant hand.

Development of Laterality and Bimanual Interference of Fine Motor Movements in Childhood and Adolescence

Drawing and handwriting are fine motor skills acquired during childhood. We analyzed the development of laterality by comparing the performance of the dominant with the nondominant hand and the effect of bimanual interference in kinematic hand movement parameters (speed, automation, variability, and pressure). Healthy subjects (n = 187, 6–18 years) performed drawing tasks with both hands on a digitizing tablet followed by performance in the presence of an interfering task of the nondominant hand. Age correlated positively with speed, automation, and pressure, and negatively with variability for both hands. As task complexity increased, differences between both hands were less pronounced. Playing an instrument had a positive effect on the nondominant hand. Speed and automation showed a strong association with lateralization. Bimanual interference was associated with an increase of speed and variability. Maturation of hand laterality and the extent of bimanual interference in fine motor tasks are age-dependent processes.

Reaction time and hand dominance

In most individuals, there is a significant difference in hand dominance and this suggests that sensorimotor tasks, such as reaction time, would demonstrate a difference in performance tasks conducted with dominant versus non-dominant hand. In this study, comparisons were made between the reaction time of the dominant to the nondominant hand, the reaction time of the male participants to that of the female participants, the reaction time variability of the dominant hand of the male participants to that of the dominant hand of female participants, and finally the reaction time variability of the nondominant hand of the male participants to that of the female participants. The study was conducted virtually with participants performing a set of instructions emailed to them. The results demonstrated that the reaction time of the dominant hand was faster than that of the nondominant hand in all participants, the reaction time of the male participants was faster than that of the female participants, the reaction time variability of the dominant hand was higher in male than in female participants, and lastly, the reaction time variability of the nondominant hand was lower for the male than in the female participants.

Nondominant hand computer mouse training and the bilateral transfer effect to the dominant hand

This study explored the effects of training computer mouse use in the nondominant hand on clicking performance of the dominant and nondominant hands. Computer mouse use is a daily operation in the workplace and requires minute hand and wrist movements developed and refined through practice and training for many years. Our study had eleven right-handed computer mouse users train their nondominant hand for 15 min a day, five days per week, for six weeks. This study found improved performance with the computer mouse in the dominant hand following nondominant hand training because of the bilateral transfer effect of training. Additionally, our study showed that the nondominant hand is capable of learning the complex movements that our dominant hand has trained for many years. Last, our research showed that nondominant hand performance decreases when the skill is not trained for over a year, but the performance is significantly higher than that prior to the original training and can be rapidly relearned. Overall, training the nondominant hand on the computer mouse will allow for improved performance in industry while allowing safer, sustainable, and more achievable work in a multitude of economies.

Is Postextracapsular Tonsillectomy Bleeding More Common on the Side of the Surgeon’s Nondominant Hand?

Objectives To determine the difference in bleeding when extracapsular tonsillectomy with electrocautery is performed on the dominant and nondominant side of the surgeon’s hands. Study Design Retrospective cohort study. Setting Academic university hospital. Methods Medical record data of patients who were admitted with posttonsillectomy bleeding from January 1, 2000, to July 31, 2017, were reviewed. Included were age, sex, surgical indication, side of posttonsillectomy bleeding, and time of bleeding. Information on the surgeon’s dominant hand was also collected. All patients underwent total extracapsular resection with electrocautery. Results Of 280 patients, 186 met the inclusion criteria, 116 (62.3%) males and 70 (37.7%) females. Ages ranged from 2 to 74 years (mean ± SD, 17 ± 13 years; median, 13 years). In 136 cases (73.1%), bleeding was on the side of the surgeon’s nondominant hand ( P < .0001). In 50 (26.9%) cases, bleeding was on the side of the surgeon’s dominant hand. The odds ratio of bleeding on the side of the surgeon’s nondominant hand compared to the dominant hand was 8.99. Conclusion The risk of bleeding following extracapsular tonsillectomy with electrocautery on the side of the surgeon’s nondominant hand is significantly higher than on the side of the dominant hand. Thus, additional caution is required when operating on the nondominant side of the oral cavity in extracapsular tonsillectomy using electrocautery. These findings raise questions regarding dexterity as a risk factor for posttonsillectomy bleeding.

Visual foreign accent in an emerging sign language

In the study of sign language phonology, little attention has been paid to the phonetic detail that distinguishes one sign language from another. We approach this issue by studying the foreign accent of signers of a young sign language – Al-Sayyid Bedouin Sign Language (ABSL) – which is in contact with another sign language in the region, Israeli Sign Language (ISL). By comparing ISL signs and sentences produced by ABSL signers with those of ISL signers, we uncover language particular features at a level of detail typically overlooked in sign language research. For example, within signs we find reduced occlusion (lack of contact), and across phrases there is frequent long distance spreading of the nondominant hand. This novel study of an emerging language in a language contact environment provides a model for comparative sign language phonology, and suggests that a community’s signature accent is part of the evolution of a phonological system.