Single-Joint Movements in Parkinson's Disease: A Pulse-Width and Pulse-Height Theory Review

The process by which the brain controls single-joint movements (SJM) is still not well understood. Some studies have defined rules describing the duration and magnitude of the agonist and antagonist muscles. Therefore, the purpose of this study was to analyze scientific publications about the electromyographic characteristics of SJM performed by patients with Parkinson's disease. A bibliographical review of the years 1989–2015 was performed using keywords such as electromyography, upper limb, and Parkinson's disease. After applying the inclusion criteria, 8 articles were included for analysis. The literature indicates that despite the lack of studies, it is possible to assume that considering the SJM, those with Parkinson's disease only control the magnitude of electromyography activation, being consistent only with the pulse-height theory control.     

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.     

Assessing Proprioception in Children: A Review

Proprioception is the subconscious and conscious awareness of the spatial and mechanical status of the musculoskeletal framework. When working with children with motor delays and sensory integrative dysfunction, occupational therapists routinely assess the client's proprioceptive system. However, currently available assessments for occupational therapists are primarily observer-based and concerns have been raised about the reliability of observer-based assessments of sensation. The author's purpose was to review measures of proprioception currently available to occupational therapists and explore direct measures of proprioception from neuroscience and rehabilitation that can be adapted for pediatric clinical use. Observer-based and direct measurements of proprioception assessments complement each other in meeting clinical needs. A better understanding of both types of evaluation will improve proprioceptive evaluation.     

情绪在危机新闻框架和团体危机回应中的作用

采用2(新闻框架类型:诱发气愤情绪或诱发悲伤情绪)×2(危机事件团体回应类型:惩罚型或补偿型)×2(团体回应中情绪感染力的呈现情况:呈现或缺乏)的被试间实验设计,探讨不同版本的危机事件新闻报道诱发出的不同情绪如何影响个体的信息加工,以及情绪反应怎样影响个体对组织随后回应策略的偏好。结果发现:气愤情绪促使公众采用启发性加工方式,悲伤情绪促使公众采用系统性加工方式;相比于悲伤情绪,气愤情绪会导致公众对公司更加负面的态度;惩罚型回应信息的可信性更高;惩罚型和补偿型回应信息使公众对企业的态度从比较消极转变为偏向积极;具有强烈情绪感染力的回应信息更容易降低气愤组对企业的责任归因程度,并进而促进公众对企业态度的改变;公众的气愤和悲伤情绪水平在接受企业回应后明显减弱,但没有达到基线水平。结果表明,在面对危机事件时,新闻框架的类型、企业对危机事件的回应方式以及回应中的情绪感染力,会结合在一起,制约公众对危机事件的知觉以及对企业的判断。     

The Moderation Role of Self‐perceived Maternal Empathy in Observed Mother–Child Collaborative Problem Solving

Based on L. S. Vygotsky's sociocultural theory, previous scaffolding studies have examined some factors associated with adjustment of parental support during collaborative problem solving. However, a factor that remains unexplored in the literature is the potential relationship between parental empathy and parental support in collaborative problem solving. The present study addresses this question through the observation of 45 preschool children and their mothers cooperating in a problem‐solving task with two levels of difficulty. Teachers rated the children's fine motor skills, and sampled mothers reported their empathy levels towards their children. Consistent with the notion of scaffolding, negative correlations were found between observed maternal verbal support (cognitive, autonomy, and emotional) and child age, and between observed maternal cognitive support and teacher reports of child motor skills. An analysis of covariance revealed significant empathy‐by‐difficulty interactions for physical and cognitive support after controlling for the effect of child motor skills. Implications of these findings are discussed in terms of the role of child motor skills and the importance of parental empathy in collaborative problem solving. Copyright © 2016 John Wiley & Sons, Ltd.     

A Study of the Impact of Informed Consent Procedures on Participant Responses in Trauma-Related Research

Researchers and ethics board members are often concerned about the possibility of adverse reactions to trauma-related research. While research has shown that participants in trauma-related studies rarely experience adverse reactions, mild short-term emotional distress is common. While a number of protections have been suggested to minimize risks for more vulnerable subgroups of participants, no research to date has tested how modifications to informed consent procedures may affect the data collected and participant reactions to the research. One-hundred and forty-five college students were separated into five conditions with different modifications to the informed consent procedures. Participants completed surveys on trauma experience, posttraumatic stress, coping, and reactions to research participation. The results showed no differences among the conditions on all outcome measures. It appears that modifications to informed consent procedures geared toward minimizing risk do not affect the quality of the data collected nor change reactions to participating in trauma-related research.     

不同情感强度正性生活事件的情感和行为反应:多模型的检验和整合

3个实验探讨情感强度不同正性生活事件对个体情感和行为反应的影响。发现:(1)面对复合正性生活事件(1高正+1低正),个体会感觉比面对1个单独的高正性情感强度事件的正性感受更低,出现平均效应,2个正性生活事件不如1个好;进一步研究发现:(2)当复合正性生活事件为异类时,出现平均效应;当事件为同类时,出现累加效应;(3)当复合正性生活事件有明显的时间特点时,个体加工符合峰-终定律的解释。     

Neurophysiology and neuroanatomy of reflexive and volitional saccades: evidence from studies of humans

This review provides a summary of the contributions made by human functional neuroimaging studies to the understanding of neural correlates of saccadic control. The generation of simple visually guided saccades (redirections of gaze to a visual stimulus or pro-saccades) and more complex volitional saccades require similar basic neural circuitry with additional neural regions supporting requisite higher level processes. The saccadic system has been studied extensively in non-human (e.g., single-unit recordings) and human (e.g., lesions and neuroimaging) primates. Considerable knowledge of this system’s functional neuroanatomy makes it useful for investigating models of cognitive control. The network involved in pro-saccade generation (by definition largely exogenously-driven) includes subcortical (striatum, thalamus, superior colliculus, and cerebellar vermis) and cortical (primary visual, extrastriate, and parietal cortices, and frontal and supplementary eye fields) structures. Activation in these regions is also observed during endogenously-driven voluntary saccades (e.g., anti-saccades, ocular motor delayed response or memory saccades, predictive tracking tasks and anticipatory saccades, and saccade sequencing), all of which require complex cognitive processes like inhibition and working memory. These additional requirements are supported by changes in neural activity in basic saccade circuitry and by recruitment of additional neural regions (such as prefrontal and anterior cingulate cortices). Activity in visual cortex is modulated as a function of task demands and may predict the type of saccade to be generated, perhaps via top-down control mechanisms. Neuroimaging studies suggest two foci of activation within FEF - medial and lateral - which may correspond to volitional and reflexive demands, respectively. Future research on saccade control could usefully (i) delineate important anatomical subdivisions that underlie functional differences, (ii) evaluate functional connectivity of anatomical regions supporting saccade generation using methods such as ICA and structural equation modeling, (iii) investigate how context affects behavior and brain activity, and (iv) use multi-modal neuroimaging to maximize spatial and temporal resolution.     

A Note on Schema and Exemplar Approaches to Motor Skill Representation in Memory

Given the need for a memory representation of well-learned motor skills, a common assumption in motor behavior is that this knowledge is stored in a central, abstracted form. Active production of motor skills has not been used in experimental designs that have provided empirical support for this view of representation, however. Much of the faith in centralized, abstracted forms of memory representation for motor skills is due to the popularity of Schmidt's schema theory, which has adapted the prototype abstraction model from category learning research to the representation of motor skills. Since schema theory was proposed, however, an alternative view that seriously questions the preeminence of the prototype abstraction model for the central representation of knowledge has arisen in the category learning literature. This particular view, termed the specific exemplar model, has led a number of researchers in cognition to develop mixed models that involve both prototypic abstraction and specific exemplar elements. This note, then, identifies what can be perceived as a gap in the empirical knowledge base in motor behavior and discusses the possibility of using the debate about representation for category learning as a stimulus for initiating a similar investigation into the representation of motor skills. A hypothetical specific exemplar model for the memory representation of motor skills is outlined, and possible empirical comparisons between this model and the schema abstraction model are suggested.     

The role of auditory context in action-effect-related motor adaptation

Previous research indicates that adding auditory effects to a (silent) action can lead to substantial efficiency gains in the performance of the action, while compromising the connection between the motor and the auditory event (e.g., by removing, or by delaying the auditory effects), leads the agent to compensate for the loss of auditory feedback by executing actions in a way which increases the probability of success or enhances feedback in other modalities, thus departing from the optimal action performance. The current study explored how this motor adaptation was affected when the quality of auditory feedback was reduced by contextual factors, while keeping the physical link between the action and auditory effect intact. In two experiments, participants elicited pure tones by pinching a force sensitive resistor (FSR). In some of the conditions action-effect contingency was reduced by intermixing externally initiated tones with the self-induced ones. Pinch-force measurements indicated that action optimization was affected by contextual factors. The influence of auditory context was the most pronounced when the discrimination of self-induced and external tones was made difficult by the similarity and temporal proximity of the self-induced and external tones. In these conditions, tone eliciting actions were more forceful in comparison to conditions in which no external tones were presented, and in comparison to conditions in which the external tones were easily distinguishable from self-induced ones. This suggests that contextual factors can induce similar motor adjustments as manipulating the physical connection between the action and its sensory consequences.