Generate,maintain, manipulate? Exploring the multidimensional nature of motor imagery

Motor imagery (MI), the mental rehearsal of a motor task, is thought to be a synergistic interaction between processes that allow for the generation, maintenance, and manipulation, of motor images. While our understanding of the multidimensional nature of MI stems from research examining various methods to assess MI ability, limited research has been conducted employing multiple assessments across participants to probe the underlying dimensions of MI. Accordingly, the current study sought to explore the multidimensional nature of MI using an exploratory approach that would allow for the dimensions of imagery to be examined and linked to each assessment measure. Specifically, participants (N = 81) underwent a battery of MI-assessments (including questionnaires, mental chronometry, a hand laterality judgment task, and a MI-based learning task), and data was analyzed via principal component analysis (PCA). Three components resulted, which were named based on which outcome measures loaded on to the component: generation, maintenance, and manipulation of motor images. We further discuss a fourth component, named ‘temporal sequencing’ of motor images, identified via the initial component solution. Concordant with previous research, we highlight the importance of employing multiple measures when assessing imagery ability prior to its use in training. Notably, this work allowed us to link assessments of MI to the different dimensions of MI, informing on the nature of MI.     

Planned Straight or Biased to Be So? The Influence of Visual Feedback on Reaching Movements

Abstract

Behavioral studies consistently find that subjects move their hand along straight paths despite considerations that suggest reaches should be curved. Literature on this topic makes it clear that the experimentally displayed feedback influences how subjects reach. Could the standard visual feedback, a displayed cursor, explain the lack of path curvature in experimental results? To address this question, we conducted three experiments to examine reach behavior in the absence of the standard visual feedback. In the first experiment, we found significant increases in curvature as visual feedback was progressively extinguished across groups. A second experiment revealed that practiced reaches became curved after the standard visual feedback was removed. A final experiment found that subjects’ reaches made before and after a brief display of visual feedback were similar, indicating a preference for specific curved trajectories. Our results suggest that the consistently straight reaches often observed could be due to a bias to move the displayed cursor straight, which when removed reveal subject-specific preferences for reaches that are often curved.     

The physiology of motor delusions in anosognosia for hemiplegia: Implications for current models of motor awareness

Right brain damaged patients sometimes deny that their left arm is paralysed or even claim to have just moved it. This condition is known as anosognosia for hemiplegia (AHP). Here, we used fMRI to study patients with and without AHP during the execution of a motor task. We found that the delusional belief of having moved was preceded by brain activation of the cortical regions that are implicated in motor control in the left intact hemisphere and in the spared motor regions of the right hemisphere; patients without anosognosia did not present with the same degree of activation. We conclude that the false belief of movement is associated with a combination of strategically placed brain lesions and the preceding residual neural activity of the fronto-parietal motor network. These findings provide evidence that the activity of motor cortices contributes to our beliefs about the state of our motor system.     

Contribution of cognitive factors to the prediction of post-traumatic stress disorder, phobia and depression after motor vehicle accidents

Past research into the psychological consequences of traumatic events has largely focused on post-traumatic stress disorder (PTSD), although other anxiety disorders and depression are also common in the aftermath of trauma. Little is known about differential predictors of these conditions. The present study investigated the extent to which theoretically derived cognitive variables predict PTSD, phobias and depression after motor vehicle accidents. The cognitive predictors were compared to a set of established, mainly non-cognitive predictors. In addition, we tested how disorder-specific the cognitive predictors are. Participants (n=101) were interviewed within a year after having been injured in a motor vehicle accident. Diagnoses of PTSD, travel phobias and depression, symptom severities and predictor variables were assessed with self-report questionnaires and structured interviews. In multiple regression analyses, the sets of cognitive variables derived from disorder-specific models explained significantly greater proportions of the variance of the symptom severities than the established predictors (PTSD 76% vs. 45%, depression 72% vs. 46% and phobia 66% vs. 40%), and than cognitive variables derived from the models of the other disorders. In addition, the majority of individual cognitive variables showed the expected pattern of differences between diagnostic groups. The results support the hypothesis that disorder-specific sets of cognitive factors contribute to the development and maintenance of PTSD, phobias and depression following traumatic events.     

Applying a Theory of Change Approach to Interagency Planning in Child Mental Health

This paper describes the use of a theory of change approach to community-based cross-agency service planning for children with serious emotional disturbance and their families. Public agency planners in Contra Costa County, California used the theory of change approach to organize service planning for a population of youth who had been arrested and involved with juvenile probation. The theory of change process described in this paper links community outcomes with planned activities with the assumptions or principles that underlie the community planning efforts. When complete, a theory of change logic model can serve as a guide for implementation, ensuring that community plans for service delivery remain true to their intent. The theory of change development process includes twelve stages and is based on a step-by-step approach. Theory of change logic models establish a context for articulating a community's shared beliefs and prompt local stakeholders to establish logical connections between the population to be served, expected results, and strategies intended to achieve those results.     

Bimanual coordination and interhemispheric interaction

Bimanual coordination of skilled finger movements requires intense functional coupling of the motor areas of both cerebral hemispheres. This coupling can be measured non-invasively in humans with task-related coherence analysis of multi-channel surface electroencephalography. Since bimanual coordination is a high-level capability that virtually always requires training, this review is focused on changes of interhemispheric coupling associated with different stages of bimanual learning. Evidence is provided that the interaction between hemispheres is of particular importance in the early phase of command integration during acquisition of a novel bimanual task. It is proposed that the dynamic changes in interhemispheric interaction reflect the establishment of efficient bimanual ‘motor routines'. The effects of callosal damage on bimanual coordination and learning are reviewed as well as functional imaging studies related to bimanual movement. There is evidence for an extended cortical network involved in bimanual motor activities which comprises the bilateral primary sensorimotor cortex (SM1), supplementary motor area, cingulate motor area, dorsal premotor cortex and posterior parietal cortex. Current concepts about the functions of these structures in bimanual motor behavior are reviewed.     

The role of collaborative planning in children's source-monitoring errors and learning.

The aim of this research was to provide empirical evidence for a cognitive process that may contribute to children's learning from another person. A cornerstone of Vygotsky's sociocultural theory is that knowledge is internalized from others; however, the cognitive processes that support this transformation are underspecified. In a series of three studies, kindergarten children (mean age 5 years 8 months) participated in a categorization task with an adult in several collaborative and noncollaborative conditions and then were tested on their memory of who had performed which actions in the task. After the memory task, children were asked to recategorize the items on their own. Source-monitoring patterns and children's learning varied across conditions according to predictions. A measure of recoding was related to children's planning language that, in turn, predicted learning among the children. The results suggest that one process that contributes to children's internalization of knowledge may involve recoding of agent information and that recoding can be indexed by source-monitoring performance.     

A Case Study of the Implementation of Outcomes-Based Funding Within a Local United Way System: Some Implications for Practicing Community Psychology

This case study provides an overview of significant organizational change within the United Way system in Franklin County/Columbus, Ohio. Franklin County is a major urban center with a population approaching 1 million. The implementation of outcomes-based funding proved to be a critical factor that served to promote change within the local United Way system. Adoption of outcomes-based funding principles resulted in significant shifts in United Way funding and major policy changes. A chronology of events and stakeholder reactions over a multiyear period are reviewed. The implications of this effort to initiate major, system-level change for the practice of community psychology are discussed.     

事件时间估计偏差理论述

人们总是倾向低估完成某一任务的时间。计划谬误理论认为,时间低估倾向的原因是人们估计时间时忽视过去完成类似任务的经验,过于关注理想的任务计划和任务情景,从而导致乐观的时间估计。但是基于该理论的一些提高时间估计精确性的策略没有达到预期效果。针对这种不足,记忆偏差理论认为,人们利用的时间记忆带有偏差,从而导致偏差的时间估计。两个理论之间引起一些争论,但如果从解释水平理论的角度可以找到其相通之处     

The relationship between reduplicated babble onset and laterality biases in infant rhythmic arm movements

This study examined changes in rhythmic arm shaking and laterality biases in infants observed longitudinally at three points: just prior to, at, and just following reduplicated babble onset. Infants (ranging in age from 4 to 9 months at babble onset) were videotaped at home as they played with two visually identical audible and silent rattles presented at midline for 1.5 min each. Rate of rattle shaking increased sharply from the pre-babble to the babble onset session; but there was no indication that this increase was specific to the right arm. This finding suggests that the link between babble onset and increased rhythmic arm activity may not be the product of language-specific mechanisms, but is rather part of a broader developmental process that is also perceptual and motor.