Bilateral Transcranial Direct Stimulation Over the Primary Motor Cortex Alters Motor Modularity of Multiple Muscles

Abstract

Transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) has been demonstrated to modulate the motor performance of both healthy individuals and patients with neuromuscular disorders. However, the effect of tDCS on motor control of multiple muscles, which is a prerequisite to change in motor performance, is currently unknown. Using dimensionality reduction analysis, we investigated whether bilateral tDCS over M1 modulates the coordinated activity of 12 muscles. Fifteen healthy men participated in this randomized, double-blind crossover study. Each participant received a 20-min sham and 2-mA stimulation bilaterally over M1 (anode on the right M1 and cathode on the left M1), with a minimum washout period of 4?days. Muscle activation and end-point kinematics were evaluated during a task where participants reached out to a marked target with non-dominant hand as fast as possible, before and immediately after tDCS application. We found decreased similarity in motor modularity and significant changes in muscle activation in a specific motor module, particularly when reaching out to a target placed within arm’s length and improved smoothness index of movement only following 2-mA stimulation. These findings indicate that clinicians and researchers need to consider the simultaneous effect of bilateral tDCS over M1 on multiple muscles when they establish tDCS protocol to change in motor performance of patients with neuromuscular deficits.     

Decision-makers use social information to update their preferences but choose for others as they do for themselves

People's risky decisions are susceptible to the social context in which they take place. Across three experiments using different paradigms, we investigated the influence of three social factors upon participants' decisions: the recipient of the decision-making outcome (self, other, or joint), the nature of the relationship with the other agent (friend, stranger, or teammate), and the type of information that participants received about others' preferences: none at all, general information about how previous participants had decided, or information about a specific partner's preference. We found that participants' decisions about risk did not differ according to whether the outcome at stake was their own, another agent's, or a joint outcome, nor according to the type of information available. Participants did, however, adjust their preferences for risky options in light of social information.     

A focus group study on the potential of autonomous vehicles as a viable transportation option: Perspectives from people with disabilities and public transit agencies

Autonomous vehicle (AV) technology is becoming one of the most promising alternatives to improve mobility for people with disabilities. Nevertheless, how people with disabilities perceive AV as transportation services has not been explored. Also, limited information exists about how public transit agencies comprehend and perceive autonomous vehicle transportation (AVT) services. This study discusses mobility issues for people with disabilities and explores the potential of AVT to serve that population, particularly those with visual impairments or physical disabilities. Researchers conducted six focus groups comprising people with disabilities (N = 23) and public transit service experts (N = 10) in Austin, Texas and Houston, Texas. Each session was audio-recorded and analyzed using conventional content analysis. This study identified people with disabilities’ mobility issues related to: (1) current transit services (including fixed-route and paratransit services) and (2) the quality of neighborhood built environments. Both people with disabilities and transit experts expected that AVT could mitigate current mobility issues, especially in improved built environments. However, participants with disabilities also expressed concerns and anxieties regarding AVT. Transit experts agreed that more targeted strategies would be needed to overcome possible barriers to AVT for people with disabilities. This study provides insights on shaping AVT strategies and policies relevant to improving mobility for people with disabilities.     

Barriers and facilitators affecting the sustainability of dialectical behaviour therapy programmes: A qualitative study of clinician perspectives

Dialectical behaviour therapy (DBT) is a psychological treatment developed for individuals experiencing chronic suicidality and high‐risk behaviours. Despite the substantial evidence supporting the effectiveness of DBT, many programmes have problems with its sustainability. The goals of the current qualitative study were to identify factors that impact the sustainability of DBT programmes within a publicly funded mental health system and identify factors that are particularly relevant for youth DBT programmes. Interviews with trained adult and youth DBT clinicians (N = 31) were conducted to explore their experiences providing DBT. Three major themes that emerged as barriers to the sustainability of DBT programmes included the following: systemic challenges, conflicts within the consultation teams and clinician burnout. Factors influencing the success of DBT programmes included the following: systemic support, clinician commitment and “buy in”, and team cohesion. Factors specific to providing DBT with youth (i.e. level of commitment, simplifying the language, and parental investment) and recommendations for sustainability for adults and youth programmes were also identified. Findings of this study provide valuable information on factors impacting DBT programmes within the unique context of a Canadian mental health service system, where community‐based services are publicly funded. These findings have clear clinical utility and can be used to generate solutions to clinicians' perceived barriers and to foster perceived facilitators within similar contexts.     

人口统计学特征对公共服务动机有什么影响?来自元分析的证据

采用元分析方法探讨人口统计学特征与公共服务动机之间的关系。经筛选, 共纳入138篇492个独立样本(N = 1078442)。结果发现, 性别、年龄、教育程度、组织任期、工作任期、职位等级和收入与公共服务动机之间均呈显著的正相关关系, 且与公共服务动机不同维度之间的关系均存在差异, 婚姻状况与公共服务动机间不存在显著的相关关系。此外, 公共服务动机测量工具、测量时间点和文化背景对部分人口统计学特征与公共服务动机之间的关系有调节作用。研究结果为人口统计学特征如何影响公共服务动机提供了较为精确的估计, 对于发展公共服务动机理论, 激励员工工作积极性, 提高公共部门服务水平都有重要意义。     

A simulation study of the degrees of freedom of movement in reaching and grasping

The question of independently controlled components in the act of reaching and grasping has attracted interest experimentally and theoretically. Data from 35 studies were recently found consistent with simulated kinematic finger and thumb trajectories optimised for minimum jerk. The present study closely reproduces those trajectories using a discrete-time model based on minimum acceleration. That model was further used to generate two-dimensional trajectories for finger and thumb to reach and grasp an elliptical object with varying position and/or orientation. Orthogonalisation of these four trajectories revealed one degree of freedom when direction of reach was constant and two degrees of freedom when direction of reach varied, irrespective of object distance and orientation. These simulations indicate that reach and grasp movements contain redundancy that is removable by formation of task-dependent synergies. As skilled movement can be planned and executed in a low dimension workspace, control of these independent components lessens central workload.     

Doctor's Expertise and Managing Discrepant Information from Other Sources in Genetic Counseling: A Conversation Analytic Perspective

The study examines a recurrent interactional pattern in genetic counseling. It describes clinical geneticists' responses in situations in which clients have presented information from other sources that is potentially discrepant with information given by the doctor. The data consists of 12 video-recorded sessions of genetic counseling in Finland, and the method is conversation analysis. There are two primary ways the doctors respond: either they accept the client's information as such, but show that it is not discrepant with the doctor's information, or they reject the client's information. In the latter case they mitigate the ‘wrongness’ of the client's information. The clinical geneticists seem to be working with a dilemma: they need to find a balance between ensuring correct understanding of the information and showing respect for the expertise of others. A particularly complex case is also analyzed and reflected on.     

Exploring dynamics of abusive lesbian relationships: preliminary analysis of a multisite,qualitative study

This paper presents preliminary results from a multisite, qualitative study on violence in lesbian relationships. A framework for conducting community-based, empowerment research that draws on theories of community psychology, feminism, and postmodernism is presented. The study was designed to understand the dynamics of abusive lesbian relationships and social service providers' responses to the abuse. Results from 80 in-depth interviews with lesbians who have experienced relationship violence are examined with a particular focus on a pattern of first relationships being abusive and a theme of shifting power dynamics. Analysis of focus group discussions with 45 feminist service providers (e.g., counselors, shelter workers, social workers, healthcare providers) reveals the difficulties in assessing the power dynamics of abusive same-sex relationships and in developing appropriate responses when relying on heterosexually gendered models developed to address men's violence against women. The preliminary results present implications both for how we theorize and research this form of violence, and for improving the practices and policies of social services that work with lesbian, gay, bisexual, and transgendered communities.