Motor Programming When Sequencing Multiple Elements of the Same Duration

Motor programming at the self-select paradigm was adopted in 2 experiments to examine the processing demands of independent processes. One process (INT) is responsible for organizing the internal features of the individual elements in a movement (e.g., response duration). The 2nd process (SEQ) is responsible for placing the elements into the proper serial order before execution. Participants in Experiment 1 performed tasks involving 1 key press or sequences of 4 key presses of the same duration. Implementing INT and SEQ was more time consuming for key-pressing sequences than for single key-press tasks. Experiment 2 examined whether the INT costs resulting from the increase in sequence length observed in Experiment 1 resulted from independent planning of each sequence element or via a separate "multiplier" process that handled repetitions of elements of the same duration. Findings from Experiment 2, in which participants performed single key presses or double or triple key sequences of the same duration, suggested that INT is involved with the independent organization of each element contained in the sequence. Researchers offer an elaboration of the 2-process account of motor programming to incorporate the present findings and the findings from other recent sequence-learning research.     

不同运动经历人群的内隐序列学习能力

考察不同运动经历人群的内隐序列学习能力。被试为上海体育学院小球运动员和非运动员;实验结合PDP,采用序列学习任务,并测试操作智商与记忆广度。结果发现,运动员在15个组段上的平均反应时、内隐学习量、自动提取贡献率上显著大于非运动员;不同水平运动员在内隐学习量上差异显著。研究结论:运动员的内隐序列学习能力显著好于非运动员,与运动水平有关,与智商无显著相关;这种内隐序列学习能力可能是某种运动能力的表现形式。     

Motor Development During the First Year: A Comparative Study

This investigation of the motor development characteristics of Brazilian infants during the 1st year of postnatal life compared the findings with those of a widely used U.S. sample (N. Bayley, 1993). Analysis of the 12 monthly assessments indicated that Brazilian infants' scores increased with age, with the greatest increase occurring over the first 8 months. As a general comparison, the results are similar to the U.S. patterns of development. However, the Brazilian sample exhibited mean scores significantly lower than the U.S. sample's in the 3rd, 4th, and 5th months. More specific analyses indicated that the difference within these months was on tasks of sitting and grasping. Possible explanations for the differences focus on variations in child-rearing practices and the influence of biological maturation in early movement behaviors.     

儿童早期精细动作技能与认知发展的关系

精细动作技能指个体主要凭借手以及手指等部位的小肌肉或小肌肉群而产生的运动, 它可以为个体提供认知经验, 丰富认知对象, 进而促进个体对事物本质的认识。当个体需要将认知资源-注意在两个或多个任务之间进行分配时, 熟练的精细动作可以节省注意资源, 为高级的认知任务更好地服务; 精细动作与认知在发展中不断相互促进, 有些动作是某些认知习得或认知练习的先决条件; 精细动作技能可以预测小学低年级的学业成绩, 尤其是阅读和数学成绩。精细动作技能和认知发展的关系具有大脑神经发育基础, 它们在某种程度上共享相同的脑区, 如小脑和前额叶。因此, 某些认知损伤的病症可以通过精细动作的训练而得到改善和治疗。     

Perceptual hysteresis as a marker of perceptual inflexibility in schizophrenia

People with schizophrenia are known to exhibit difficulties in the updating of their current belief states even in the light of disconfirmatory evidence. In the present study we tested the hypothesis that people with schizophrenia could also manifest perceptual inflexibility, or difficulties in the updating of their current sensory states. The presence of perceptual inflexibility might contribute both to the patients’ altered perception of reality and the formation of some delusions as well as to their social cognition deficits. Here, we addressed this issue with a protocol of auditory hysteresis, a direct measure of sensory persistence, on a population of stabilized antipsychotic-treated schizophrenia patients and a sample of control subjects. Trials consisted of emotional signals (i.e., screams) and neutral signals (i.e., spectrally-rotated versions of the emotional stimuli) progressively emerging from white noise – Ascending Sequences – or progressively fading away in white noise – Descending Sequences. Results showed that patients presented significantly stronger hysteresis effects than control subjects, as evidenced by a higher rate of perceptual reports in Descending Sequences. The present study thus provides direct evidence of perceptual inflexibility in schizophrenia.     

Motor Performance in the Third,Not the Second Month,Predicts Further Motor Development

ABSTRACT. The aim was to verify if motor performance at second or third month of life better predicts further development. The global motor development was assessed by a neurologist and by a physiotherapist in 111 children at 2, 3, 6, and 9 months. At 2 and 3 months a physiotherapist also performed the assessment of qualitative elements. The physiotherapeutic assessment in the third month showed higher compatibility with the neurological assessment. Proper motor performance at third month could ensure the level of at least 7 months in the ninth month of life. Qualitative score above 7 of 15 points in the third month ensured proper development in ninth month. Third month of life is a better predictor of further motor development.     

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.     

The Effects of Brain Lateralization on Motor Control and Adaptation

ABSTRACT

Lateralization of mechanisms mediating functions such as language and perception is widely accepted as a fundamental feature of neural organization. Recent research has revealed that a similar organization exists for the control of motor actions, in that each brain hemisphere contributes unique control mechanisms to the movements of each arm. The authors review present research that addresses the nature of the control mechanisms that are lateralized to each hemisphere and how they impact motor adaptation and learning. In general, the studies suggest an enhanced role for the left hemisphere during adaptation, and the learning of new sequences and skills. The authors suggest that this specialization emerges from a left hemisphere specialization for predictive control—the ability to effectively plan and coordinate motor actions, possibly by optimizing certain cost functions. In contrast, right hemisphere circuits appear to be important for updating ongoing actions and stopping at a goal position, through modulation of sensorimotor stabilization mechanisms such as reflexes. The authors also propose that each brain hemisphere contributes its mechanism to the control of both arms. They also discuss the potential advantages of such a lateralized control system.     

视知觉压力在基本心理能力老化中的作用

信息降格说认为, 感觉功能老化使认知系统难以获得良好的信息输入, 并必须牺牲有限的认知资源获得更好的刺激信息, 使能用于认知加工的资源不足, 造成认知老化。为探讨感觉功能对基本心理能力老化的作用, 该研究采用2(年龄组：年轻、老年组)×4(视知觉压力水平：高、中、低、无噪音)的混合设计, 考察年轻、老年组在相同视知觉压力下基本心理能力的年龄差异。结果发现和无噪音条件相比, 相同视知觉压力下基本心理能力(数字能力、归纳推理能力)的年龄差异减小, 甚至消失, 一定程度上支持信息降格说。视觉功能衰退可能是影响基本心理能力老化的重要因素, 但这种作用受认知资源的调节。     

Motor Cortex Plasticity in Children With Spastic Cerebral Palsy: A Systematic Review

A review of the literature was performed to answer the following questions: Does motor cortex excitability correlate with motor function? Do motor cortex excitability and cortex activation change after a rehabilitation program that results in improvements in motor outcomes? Can the 10–20 electroencephalography (EEG) system be used to locate the primary motor cortex when employing transcranial direct current stimulation? Is there a bihemispheric imbalance in individuals with cerebral palsy similar to what is observed in stroke survivors? the authors found there is an adaptation in the geometry of motor areas and the cortical representation of movement is variable following a brain lesion. The 10–20 EEG system may not be the best option for locating the primary motor cortex and positioning electrodes for noninvasive brain stimulation in children with cerebral palsy.     

Development of sensorimotor synchronization abilities: Motor and cognitive components

The aim of the present study was to examine both the development of sensorimotor synchronization in children in the age range from 5 to 8 years and the involvement of motor and cognitive capacities. Children performed a spontaneous motor tempo task and a synchronization–continuation task using an external auditory stimulus presented at three different inter-stimulus intervals: 500, 700, and 900 ms. Their motor and cognitive abilities (short-term memory, working memory, and attention) were also assessed with various neuropsychological tests. The results showed some developmental changes in synchronization capacities, with the regularity of tapping and the ability to slow down the tapping rate improving with age. The age-related differences in tapping were nevertheless greater in the continuation phase than in the synchronization phase. In addition, the development of motor capacities explained the age-related changes in performance for the synchronization phase and the continuation phase, although working memory capacities were also involved in the interindividual differences in performance in the continuation phase. The continuation phase is thus more cognitively demanding than the synchronization phase. Consequently, the improvement in sensorimotor synchronization during childhood is related to motor development in the case of synchronization but also to cognitive development with regard to the reproduction and maintenance of the rhythm in memory.     

Highs and Lows in Motor Control Development

Abstract

Motor control is classically described as relying on two components: anticipatory control (feedforward processing) and online control (feedback processing). Here we aimed to unveil the developmental steps of both feedback and feedforward control in 5–10 years old children, using a simple and ecological task. We manipulated object’s weight in a reach-to-displace paradigm. When the weight was known before lifting it, anticipatory processes were quantifiable during the reaching phase. Conversely, an unknown weight triggered online corrections during the displacing phase. Movement kinematics revealed that children anticipate this objet property as young as 5 y-o. This anticipation becomes adequate around 7 y-o and is paralleled by poor online corrections. This simple yet relevant paradigm should allow quantifying deviations from neurotypical patterns in disorders of motor control.     

The Effect of Interpolated Motor Activities in Short-Term Motor Memory

This experiment examined the effect of an interpolated motor response on short-term retention of a blind positioning movement. The interpolated response was varied in degree of similarity to the response length (± 25, ± 50, and ± 100 mm.), in number of repetitions (0, 1, or 5), and in temporal position (immediate or delayed), with a retention interval of 25 sec. Absolute error was not affected but a systematic change in response bias due to interpolated motor activity was found. When an interpolated response was longer than the response length, the tendency to undershoot decreased. The defay of the interpolated response was relatively more important than the number of repetitions in producing a positive shift in response bias. These results are interpreted as evidence for a form of interference in short-term motor memory.     

The Motor System Computes Well but Remembers Poorly

The psychological approach to human voluntary movements advocated by F. Mechsner (2004) can be aligned with the view that motor commands are generated afresh but are not retrieved from memory. This movement-generation hypothesis gains indirect support in the findings Mechsner reviewed and obtains more direct support from the results of studies of memory for movement and computational modeling of motor planning.     

Cortical Cell Assemblies: A Possible Mechanism for Motor Programs

The concept of a motor program has been used to interpret a diverse range of empirical findings related to preparation and initiation of voluntary movement. In the absence of an underlying mechanism, its explanatory power has been limited to that of an analogy with running a stored computer program. We argue that the theory of cortical cell assemblies suggests a possible neural mechanism for motor programming. According to this view, a motor program may be conceptualized as a cell assembly, which is stored in the form of strengthened synaptic connections between cortical pyramidal neurons. These connections determine which combinations of corticospinal neurons are activated when the cell assembly is ignited. The dynamics of cell assembly ignition are considered in relation to the problem of serial order. These considerations lead to a plausible neural mechanism for the programming of movements and movement sequences that is compatible with the effects of precue information and sequence length on reaction times. Anatomical and physiological guidelines for future quantitative models of cortical cell assemblies are suggested. By taking into account the parallel, re-entrant loops between the cerebral cortex and basal ganglia, the theory of cortical cell assemblies suggests a mechanism for motor plans that involve longer sequences. The suggested model is compared with other existing neural network models for motor programming.     

The Mediating Role of Social Skills in the Relationship between Motor Ability and Internalizing Symptoms in Pre‐primary Children

Impaired motor development can deprive a child of constructive engagement in early motor activities and thus diminish opportunities for the acquisition of key cognitive, social and emotional abilities. The aim of the current study was to test a model where social skills mediate the relationship between motor ability and internalizing symptoms in pre‐primary children. A cross‐sectional research design was employed to assess the mediation model using data from 234 boys and 241 girls aged 4 to 6 years. Structural equation modelling provided support for the mediating role of social skills as assessed by the child's teacher. Replication of these findings in longitudinal studies, elucidating how social skills relate to motor impairment, could have implications for the prevention of psychopathology in young children with motor impairment. Copyright © 2012 John Wiley & Sons, Ltd.     

Influence of Response Similarity on Interference in Perceptual Motor Learning

Motor interference was measured in terms of average response time in sorting 15 pairs of cards, each pair containing words which were either unrelated or identical but printed in different colors. The two words of each pair were used in labeling two cubicles in such a way that they were apart by 0, 1, 2, or 3 intervening cubicles in quasirandomly chosen directions. Interference was inversely related to response similarity, but this relationship may not appear in the absence of sufficient stimulus similarity. The findings are interpreted in the light of a hypothesis which views motor interference as a tendency for responses to deflect from their own courses and be pulled towards those of other responses with which they are at conflict.     

Transfer of Work Decrement in Motor Learning

Two experiments tested the hypothesis that the decremental effects of massed practice are due to the development of a negative drive (Hull’s I_r). The results indicated that the decremental effects of massed practice on either the pursuit rotor or the two-hand coordinator do not transfer to depress performance or reminiscence on the other task. The results did not support Hull’s drive interpretation but were explained by theories attributing decrement to a decreased level of arousal.     

Children's Road Crossing: A Window Into Perceptual–Motor Development

ABSTRACT— Most research on perceptual–motor development has focused on changes occurring during infancy and toddlerhood. In this paper, we describe our work on the development of perceptual–motor development during late childhood and early adolescence in the context of an important applied problem: bicycling across traffic-filled roads. Specifically, we have examined the gaps between cars that children and adults accept when bicycling across intersections, using an immersive, interactive bicycling simulator. This work highlights both methodological advances in using immersive, interactive virtual environments to study perceptual–motor functioning as well as theoretical advances in understanding the problem of moving the self in relation to other moving objects. We conclude with ideas for future research and practical implications of this work.