儿童的人际运动同步

人际运动同步是一种“社会胶粘剂”,能促进儿童产生更多的亲社会行为。儿童的人际运动同步能力随着年龄的增长不断提升,其同步表现受到运动方式、节奏刺激类型、同步对象等因素影响。在人际运动同步过程中,时间感知、运动计划和运动执行三大认知因素参与其中,既制约着个体同步能力的发展,也影响个体同步的表现。孤独症作为一种神经发育性障碍,孤独症儿童表现出异常的人际运动同步。未来的研究不仅要探讨孤独症儿童人际运动同步的异常机制,还要更多关注人际运动同步训练在孤独症群体中的实际应用和干预效果。     

Investigation of fine motor performance in children younger than 36-month-old using PDMS-2 and Bayley-III

ABSTRACT

The aim of the study was to investigate the concurrent validity of fine motor (FM) development scores between the Peabody Developmental Motor Scales, Second Edition (PDMS-2), and Bayley Scale of Infant and Toddler Development, Third Edition (Bayley-III). Both tests were administered to 223 children aged 13–36 months with suspected developmental delays from a medical centre. Concurrent validity and agreement of FM delay were assessed. The Bayley-III FM scale scores (FMSS) and motor composite quotients were moderately correlated with PDMS-2 FM quotients. The agreement of FM delay between the two instruments was excellent (Kappa coefficient value = .80) in children aged 13–18 months and good in children aged 19–36 months. When using PDMS-2 as the reference standard, Bayley-III (FMSS < 7) identified fewer children aged 19–24 months as delayed but more in children aged 25–36 months as delayed. When adjusting the cut-off point of Bayley-III FMSS to 8 for children aged 19–24 months and to 6 for children aged 25–36 months, the agreement improved between these two instruments. FM delays might be underestimated solely using Bayley-III in children aged 19–24 months. Additional tests, such as PDMS-2 should be considered to avoid delays in accessing early intervention services.     

Memory systems and the control of skilled action

ABSTRACT

In keeping with the dominant view that skills are largely automatic, the standard view of memory systems distinguishes between a representational declarative system associated with cognitive processes and a performance-based procedural system. The procedural system is thought to be largely responsible for the performance of well-learned skilled actions. Here we argue that most skills do not fully automate, which entails that the declarative system should make a substantial contribution to skilled performance. To support this view, we review evidence showing that the declarative system does indeed play a number of roles in skilled action.     

Knowing what you are doing: Action-demonstratives in unreflective action

Almost everything that we do, we do by doing other things. Even actions we perform without deliberation or conscious planning are composed of ‘smaller’, subsidiary actions. But how should we think of such subsidiary actions? Are they fully-fledged intentional actions (in the sense of things that we do for reasons) in their own right? In this paper I defend an affirmative answer to this question, against a recently influential form of scepticism. Drawing on a distinctive kind of ‘action-demonstrative’ representation, I show that the sceptic's arguments do not go through.     

Instruction Modes for Motor Control Skills Acquisition: A Randomized Controlled Trial

Abstract

The objective was to compare two different instruction modes used to teach patients with nonspecific chronic low back pain (CLBP) to perform a lumbar motor control task. The three intervention instruction modes used were: common verbal explanation of a motor task based on a motor control therapeutic exercise (MCTE-control group), MTCE instructed using motor imagery (MI) and MCTE instructed using tactile feedback (TF). The main outcome measure was lumbar motor control of the neutral position test. Forty-eight patients with CLBP were randomly allocated into three groups of 16 patients per group. The MI strategy was the most effective mode for developing the motor control task in an accurate and controlled manner, obtaining better outcomes than TF or verbal instruction.     

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.     

Action experience in infancy predicts visual-motor functional connectivity during action anticipation

Despite substantial evidence indicating a close link between action production and perception in early child development, less is known about how action experience shapes the processes of perceiving and anticipating others’ actions. Here, we developed a novel approach to capture functional connectivity specific to certain brain areas to investigate how action experience changes the networks involved in action perception and anticipation. Nine- and-12-month-old infants observed familiar (grasping) and novel (tool-use) actions while their brain activity was measured using EEG. Infants’ motor competence of both actions was assessed. A link between action experience and connectivity patterns was found, particularly during the anticipation period. During action anticipation, greater motor competence in grasping predicted greater functional connectivity between visual (occipital alpha) and motor (central alpha) regions relative to global levels of whole-brain EEG connectivity. Furthermore, visual and motor regions tended to be more coordinated in response to familiar versus novel actions and for older than younger participants. Critically, these effects were not found in the control networks (frontal-central; frontal-occipital; parietal-central; parietal-occipital), suggesting a unique role of visual-motor networks on the link between motor skills and action encoding.

Highlights

• Infants’ motor development predicted functional connectivity patterns during action anticipation.
• Faster graspers, and older infants, showed a stronger ratio of visual-motor neural coherence.
• Overall whole-brain connectivity was modulated by age and familiarity with the actions.
• Measuring inter-site relative to whole-brain connectivity can capture specific brain-behavior links.
• Measures of phase-based connectivity over time are sensitive to anticipatory action.