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151.
Presentation of two kinds of materials in working memory (visual and acoustic), with the requirement to attend to one or both modalities, poses an interesting case for working memory development because competing predictions can be formulated. In two experiments, we assessed such predictions with children 7–13 years old and adults. With development, the ability to hold more information in the focus of attention could lead to an increase in the size of the trade‐off between modalities; if attention can hold A items during unimodal‐attention trials, then on average attention should hold A/2 of those same items during bimodal‐attention trials. If A increases with age, so would the dual‐task cost, A/2. The results clearly ruled out that possibility. It was the modality‐ or code‐specific components of working memory that improved with age and not the central component. We discuss various mechanisms that could have produced these results, including alternative attention‐based mechanisms. The findings point to a rich field for continued research.  相似文献   
152.
Patients and health care consumers can obtain access to their “raw,” or uninterpreted, genetic data from direct-to-consumer genetic testing companies, researchers, or providers and pursue self-directed analysis via third-party interpretation tools. Yet relatively little is known about the nature of currently available interpretation tools or the motivations of tool developers. We conducted a structured content analysis of 23 third-party interpretation tool websites and supporting information, tracking features such as types of information returned, modes of generating and presenting that information, and privacy and security measures. We additionally conducted qualitative interviews with a subset of 10 tool developers. A majority of tools (16 of 23, or 70%) offer some type of health or wellness-related information, often extracted from publicly available variant annotation databases. Half of those interviewed characterized their activities as “bridging” users to the scientific literature rather than interpretation, for which they gave a variety of scientific, ethical, and regulatory justifications. The scale, heterogeneity, and complexity of information available from third-party interpretation are unprecedented. While developers aim to enlighten and empower tool users, interpretation-free “bridging” to rapidly evolving databases may instead impose burdens on genetic counselors and other health care providers asked to provide further contextualization and explanation.  相似文献   
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The primary goal of this study was to examine the relations between limb control and handedness in adults. Participants were categorized as left or right handed for analyses using the Edinburgh Handedness Inventory. Three-dimensional recordings were made of each arm on two reach-to-place tasks: adults reached to a ball and placed it into the opening of a toy (fitting task), or reached to a Cheerio inside a cup, which they placed on a designated mark after each trial (cup task). We hypothesized that limb control and handedness were related, and we predicted that we would observe side differences favoring the dominant limb based on the dynamic dominance hypothesis of motor lateralization. Specifically, we predicted that the dominant limb would be straighter and smoother on both tasks compared with the nondominant limb (i.e., right arm in right-handers and left arm in left-handers). Our results only partially supported these predictions for right-handers, but not for left-handers. When differences between hands were observed, the right hand was favored regardless of handedness group. Our findings suggest that left-handers are not reversed right-handers when compared on interlimb kinematics for reach-to-place tasks, and reaffirm that task selection is critical when evaluating manual asymmetries.  相似文献   
154.
Family adversity has been associated with children’s bullying behaviors. The evidence is, however, dominated by mothers’ perceptions of the family environment and a focus on mothers’ behaviors. This prospective population-based study examined whether children’s bullying behaviors were associated with mother- and father-reported family adversity, assessed before and after child birth. Peer-nominations were used to assess bullying behaviors of 1298 children in elementary school (mean age 7.5 years). The following paternal risk factors were prospectively associated with children’s bullying behaviors: (1) father-reported prenatal family distress, (2) fathers’ hostility at preschool age, and (3) fathers’ harsh disciplinary practices at preschool age, but effect sizes were relatively small. The effect of maternal risk factors was less consistent, only mother-reported family distress in childhood was associated with children’s bullying behaviors. The associations were independent of background family risk factors (i.e., life stress, contextual factors, and other background factors such as parental education and risk taking record) and early childhood externalizing problems. Moreover, our results indicated that father-reported family adversity predicted children’s bullying behaviors over and above the background family risk factors, early childhood externalizing problems and mother-reported family adversity. We also demonstrated that the association of fathers’ prenatal hostility and family distress with subsequent bullying behavior of their child at school was partly mediated by fathers’ harsh disciplinary practices at preschool age. Our findings highlight the importance of fathers’ behaviors in the development of children’s bullying behaviors.  相似文献   
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This collective case study investigated the experiences of bilingual counselors‐in‐training who assessed school‐wide cultural competence in public schools. Analysis and interpretation of data resulted in the identification of 5 themes: eye‐opening experiences, recognition of strengths, the role of school leaders, road maps for change, and empowering marginalized groups. Implications and recommendations are discussed. Este estudio de caso colectivo investigó las experiencias de consejeros bilingües en formación que evaluaron la competencia cultural institucional en escuelas públicas. El análisis e interpretación de los datos dieron como resultado la identificación de 5 temas: experiencias reveladoras, reconocimiento de puntos fuertes, el papel de los líderes académicos, hojas de ruta para el cambio y empoderamiento de grupos marginalizados. Se discuten las implicaciones y recomendaciones.  相似文献   
157.
Military personnel endure rigorous and demanding man-hours designated to monitoring and locating targets in tasks such as cyber defense and Unmanned Aerial Vehicle (UAV) operators. These tasks are monotonous and repetitive, which can result in vigilance decrement. The objective of the study was to implement a form of noninvasive brain stimulation known as transcranial DC stimulation (tDCS) over the left frontal eye field (LFEF) region of the scalp to improve cognitive performance. The participants received anodal and cathodal stimulation of 2 mA for 30 min as well as placebo stimulation on 3 separate days while performing the task. The findings suggest that anodal and cathodal stimulation significantly improves detection accuracy. Also, a correlation was detected between percent of eye closure (PERCLOS) and blinking frequency in relation to stimulation condition. Our data suggest that tDCS over the LFEF would be a beneficial countermeasure to mitigate the vigilance decrement and improve visual search performance.  相似文献   
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