Training of 7-month-old infants’ manual object exploration skills: Effects of active and observational experience

In the present study, a fine motor training was developed and evaluated in which infants were trained to manually explore objects in an advanced manner. Fifty 7-month-old infants were randomly assigned to three different training conditions: (1) to an active manual exploration training, in which they learned to explore objects efficiently, (2) to an observational manual exploration training, in which they observed how an adult performed sophisticated actions on objects, or (3) to a control group receiving no training. The results impressively indicate that infants with a low level of object exploration skill prior to the training showed the most training effects as compared to infants with proficient object exploratory actions. Interestingly, this differential training effect was true for both the active and observational training, highlighting the role of social learning in infancy. Importantly, our study shows for the first time the impact of normal individual variation in infants’ manual object exploration skills on the effects of a fine motor training.     

Anticipating ankle inversion perturbations during a single-leg drop landing alters ankle joint and impact kinetics

Anticipatory responses to inversion perturbations can prevent an accurate assessment of lateral ankle sprain mechanics when using injury simulations. Despite recent evidence of the anticipatory motor control strategies utilized during inversion perturbations, kinetic compensations during anticipated inversion perturbations are currently unknown. The purpose of this investigation was to examine the influence of anticipation to an inversion perturbation during a single-leg drop landing on ankle joint and impact kinetics. Fifteen young adults with no lateral ankle sprain history completed unanticipated and anticipated single-leg drop landings onto a 25° laterally inclined platform from a height of 30 cm. One-dimensional statistical parametric mapping (SPM) was used to analyze net ankle moments and ground reaction forces (GRF) during the first 150 ms post-landing, while peak GRFs, time to peak GRF, peak and average loading rates were compared using a dependent samples t-test (p ≤ 0.05). Results from the SPM analysis revealed significantly greater plantar flexion moment from 58 to 83 ms post-landing (p = 0.004; d = 0.64–0.77), inversion moment from 89 to 91 ms post-landing (p = 0.050; d = 0.58–0.60), and medial GRF from 62 to 97 ms post-landing (p < 0.001; d = 1.00–2.39) during the unanticipated landing condition. Moreover, significantly greater peak plantarflexion (p < 0.001; d = 1.10) and peak inversion moment (p = 0.007; d = 0.94), as well as greater peak (p = 0.002; d = 1.03) and average (p = 0.042; d = 0.66) medial loading rates, were found during the unanticipated landing condition. Our findings suggest alterations to ankle joint and impact kinetics occur during a single-leg drop landing when inversion perturbations are anticipated. Researchers and practitioners using drop-landings onto a tilted surface to assess lateral ankle sprain injury risk should consider implementing protocols that mitigate anticipatory responses.     

Relationships among motor skill,perceived self-competence,fitness, and physical activity in young adults

PurposeThis large-scale, exploratory study sought to examine the associations between motor skill proficiency (MSP), perceived self-competence (PC), physical fitness (PF), and self-reported physical activity (PA) to assess the assumption that relationships among these variables found in childhood and adolescence persist into young-adulthood. Specifically, predictors of PF and PA were assessed. Additionally, the contributions body mass index (BMI) and gender made to these relationships, as well as that of process- versus product-oriented motor skills data, were studied. Finally, how these relationships differed by gender was explored.MethodsParticipants’ (n = 448) MSP was assessed using select measures from the TGMD-2 and the BOT-2, while PF was evaluated using the FitnessGram. Participants also completed surveys to assess PC (SPPCS), PA (past-week MAQ), and demographic information. Height and weight were collected to calculate BMI.ResultsModels predicting physical fitness had good fit to the observed data, with perceived athletic competence, locomotor skill, upper-limb coordination, BMI, and gender accounting for about 75% (R² = 0.748) of aerobic PF variance and about 48% (R² = 0.476) of variance in push-up performances. About 18% (R² = 0.178) of variance in curl-up performances was predicted by perceived athletic competence, locomotor skill, upper-limb coordination, and PA. The PA model demonstrated weaker predictive power, with only about 10% (R² = 0.097) of variance explained. When considering male and female models separately, female models demonstrated better fit when predicting all PF and PA outcome variables. BMI and gender operated as significant predictors to differing degrees across the various models.ConclusionsThere is compelling evidence to believe relationships found among MSP, PC, PF, and PA in childhood and adolescence also exist in early adulthood. However, differences in the roles of gender and physical fitness versus physical activity are likely to exist.     

Intervention,stimulus control,and generalization effects of response interruption and redirection on motor stereotypy

This study evaluated the effects of response interruption and redirection (RIRD) on motor stereotypy (hand and body movements) in a child with neurodevelopmental disorders. We also assessed whether a stimulus paired with RIRD could acquire inhibitory control when tested during nonintervention conditions. Compared with baseline phases in a reversal design, RIRD decreased both hand and motor stereotypies, and there was evidence of stimulus control. Extending RIRD to a second setting was also effective. The care providers responsible for intervention implemented RIRD with fidelity, and they rated the procedure positively. Clinical and research implications from these findings are discussed.     

Movement segmentation and visual perturbation increase developmental differences in motor control and learning

We examined the developmental differences in motor control and learning of a two‐segment movement. One hundred and five participants (53 female) were divided into three age groups (7–8 years, 9–10 years and 19–27 years). They performed a two‐segment movement task in four conditions (full vision, fully disturbed vision, disturbed vision in the first movement segment and disturbed vision in the second movement segment). The results for movement accuracy and overall movement time show that children, especially younger children, are more susceptible to visual perturbations than adults. The adults’ movement time in one of the movement segments could be increased by disturbing the vision of the other movement segment. The children's movement time for the second movement segment increased when their vision of the first movement segment was disturbed. Disturbing the vision of the first movement segment decreased the percentage of central control of the second movement in younger children, but not in the other two age groups. The children's normalized jerk was more easily increased by visual perturbations. The children showed greater improvement after practice in the conditions of partial vision disturbance. As the participants’ age increased, practice tended to improve their feedforward motor control rather than their feedback motor control. These results suggest that children's central movement control improves with age and practice. We discuss the theoretical implications and practical significance of the differential effects of visual perturbation and movement segmentation upon motor control and learning from a developmental viewpoint.     

Impaired sequential and partially compensated probabilistic skill learning in Parkinson's disease

The striatal dopaminergic dysfunction in Parkinson's disease (PD) has been associated with deficits in skill learning in numerous studies, but some of the findings remain controversial. Our aim was to explore the generality of the learning deficit using two widely reported skill learning tasks in the same group of Parkinson's patients. Thirty-four patients with PD (mean age: 62.83 years, SD: 7.67) were compared to age-matched healthy adults. Two tasks were employed: the Serial Reaction Time Task (SRT), testing the learning of motor sequences, and the Weather Prediction (WP) task, testing non-sequential probabilistic category learning. On the SRT task, patients with PD showed no significant evidence for sequence learning. These results support and also extend previous findings, suggesting that motor skill learning is vulnerable in PD. On the WP task, the PD group showed the same amount of learning as controls, but they exploited qualitatively different strategies in predicting the target categories. While controls typically combined probabilities from multiple predicting cues, patients with PD instead focused on individual cues. We also found moderate to high correlations between the different measures of skill learning. These findings support our hypothesis that skill learning is generally impaired in PD, and can in some cases be compensated by relying on alternative learning strategies.     

情绪即社会信息模型述评

情绪即社会信息(EASI)模型提出,个体对他人的情绪信息加工具有两种方式:情感反应与推断加工。认识动机水平及不同的社会情境会影响两种加工的强度,进而影响个体的决策。该模型在谈判、领导者和最后通牒、独裁者博弈研究中获得了直接和间接的实证支持。心理理论与移情的新近神经生理研究成果也有助于深入探索该模型的神经生理基础。该模型具有很强的应用潜力,但形成时间尚短,需要进一步探索并应用到实践领域中去。     

动允直接知觉的共鸣原理

传统认知理论认为我们只能间接知觉动允,而生态认知心理学则认为对动允的知觉是个体与环境信息直接共鸣的过程。生态认知心理学首先判定动允并不是存在于我们头脑中的认识,而是实际存在于个体-环境系统中的事实,对动允的直接知觉就是对动允的检测而非推测,是对动允信息的拾取而非对记忆内容的提取。这种直接知觉表现为身体的相关动作机制（动作神经元、肌肉组织等）与环境中动允信息的共鸣。进化与学习在共鸣的形成与发展中具有重要作用。     

Motor Improvement Using Motion Sensing Game Devices for Cerebral Palsy Rehabilitation

The authors aimed to investigate the effects of an intervention based on interactive game set with the movement sensor Kinect on children with cerebral palsy (CP). Twenty-eight participants were recruited. Their age was between 3 and 12 years old, and rated as level I, II, or III on the Gross Motor Function Classification System. They played two games from the Xbox 360 Kinect system and were evaluated using the Gross Motor Function Measure (GMFM) after a period of 8 weeks. The intervention led to significant motor function improvement as increase of the global scores on the GMFM (p < .001). Rehabilitation interventions using the Xbox 360 Kinect interactive games may represent useful tools for children with CP.