Journal of Motor Behavior最新文献

Adopting a postural configuration may be regarded as preparation for the performance of an upcoming movement. However, it is unclear how different postural configurations affect motor performance. The aim of the current study was to examine how body posture - sitting versus standing - influences fast and accurate planar point-to-point hand movements. Twenty-three healthy adults performed a "Go/No-go" paradigm while doing repetitive point-to-point movements. Arousal levels, which may change due to the change in posture, were independently manipulated by using a sham threat of electrical stimulation. Upper limb kinematics, center of pressure displacement, and galvanic skin responses were recorded in four test conditions: sitting and standing with and without arousal manipulation. Descriptive performance measures were computed and analyzed using multiple analyses of variance. A difference in arousal level was observed in the two conditions with the arousal manipulation, but no difference in arousal level was found between sitting and standing. Center of pressure displacement onset was found to be earlier in the two standing conditions compared to those in sitting. No difference was found in upper limb performance between the two postures, nor due to the arousal manipulation. We concluded that under the tested conditions, body posture does not appear to affect upper limb performance.

A holistic focus (HF) has been found to significantly improve performance over an internal focus (IF), in a similar way to an external focus (EF). There is a need to understand the effectiveness of a HF by investigating kinematic and kinetic outcome measures. 19 college-aged adults performed 12 vertical jumps under four conditions in a counterbalanced design. The conditions were, IF, EF, HF, and control, or no focus condition. All participants performed the vertical jumps on a force plate with 16 reflective markers placed on the lower extremities. Separate repeated measures ANOVAs with Sidak post-hoc were used to analyze jump height, flight height, peak force, takeoff velocity, and knee and hip flexion. A significant main effect for jump height was observed (p < 0.001). HF and EF jumped significantly higher than IF (p < 0.001; p < 0.001). EF also jumped significantly higher than control (p<.05). No significant main effects were observed for any kinematic or kinetic dependent variables. The results of this experiment support previous research by observing performance benefits of HF and EF over an IF. However, the benefits of HF and EF cannot be attributed to the kinetic or kinematic changes.

This study investigates the impact of self-talk and practice distribution on motor memory encoding and consolidation in adolescent males (aged 11-14). Despite extensive research on motor memory consolidation, few studies explore how self-talk and practice distribution together impact memory retention, particularly in adolescent athletes. This study aims to address this gap by exploring the combined effects of self-talk and practice distribution on motor memory. Participants (n = 80) were randomly assigned to six groups (instructional/motivational self-talk and control in both massed and distributed practice) and subjected to short pass accuracy test, which required participants to pass a ball within specified zones for scoring." The study examined acquisition and retention at 30 min, 24 h, and 72 h post-training. Distributed practice groups demonstrated superior encoding during initial learning compared to massed practice groups. Groups using self-talk outperformed control groups. Moreover, those employing self-talk showed better resistance to forgetfulness during consolidation. This research highlights the complex interaction between motor memory encoding, consolidation, and practice session strategies. It underscores the significance of self-talk as a cognitive tool in enhancing performance and skill development, particularly in adolescent males. These insights have implications for improving athletes' abilities and emphasize the importance of cognitive solutions and psychological skills.

Deficits in internal modeling have been suggested as a key factor contributing to the motor control and coordination challenges experienced by children with DCD. Recently, virtual reality (VR) technology has emerged as a promising tool for enhancing the acquisition and learning of motor skills. Therefore, the primary aim of this study was to investigate the effects of VR-based interventions on internal modeling and object control skills in children with DCD. The present study employed a quasi-experimental design, incorporating a pretest, post-test, and two-month follow-up. The sample consisted of 40 female students aged 7 to 10 years, selected based on DSM-5 criteria and randomly assigned to either a VR training program or a control group. Predictive internal modeling was assessed using continuous relative phase (CRP) through a visuomotor adaptation task, while object control skills were evaluated using the TGMD-2 test. The experimental group underwent an 8-week VR-based training program comprising 16, 30-minute sessions using task-oriented Xbox Kinect 360 games. The control group received no intervention. Results indicated that VR training significantly improved the acquisition of CRP (p = 0.037), with the experimental group demonstrating superior transfer of these skills to object control tasks compared to controls (p < 0.001). The observed reduction in CRP suggests that VR training facilitated the development of internal models in children with DCD. Furthermore, enhancements in object control skills evidenced the capacity of these children to apply and generalize acquired predictive internal models. However, despite these advancements, participants continued to exhibit compensatory strategies characterized by variability and inaccuracy, indicating persistent challenges in internal model updating.

Visual-motor illusion (VMI) is a kinesthetic illusion produced by viewing an image showing joint motion. VMI with enhanced joint movement intensity (power-VMI; P-VMI) is expected to activate a wide range of motor association brain regions, and when combined with electrical stimulation that activates the motor sensory cortex, further activation of brain activity can be expected. This study aimed to verify the effectiveness of VMI using functional near-infrared spectroscopy to confirm brain activity during combined P-VMI and electrical stimulation. Brain activity was measured in 15 healthy adults during three tasks performed on the left ankle joint: P-VMI with electrical stimulation, P-VMI alone, and electrical stimulation alone. The tasks were performed randomly on a single participant. Brain activity was measured during each task using a protocol comprising 15 s of rest, 30 s of task performance, and 30 s of follow-up. Regions of interest included motor-related areas. The results showed that P-VMI alone activated the right superior parietal lobule and left supramarginal gyrus more than P-VMI combined with electrical stimulation. These findings suggest that P-VMI and sensory-threshold electrical stimulation do not necessarily complement each other in enhancing brain activity, as P-VMI alone shows greater activation in specific motor-related brain regions.