Examining links between anxiety, reinvestment and walking when talking by older adults during adaptive gait

Falls by older adults often result in reduced quality of life and debilitating fear of further falls. Stopping walking when talking (SWWT) is a significant predictor of future falls by older adults and is thought to reflect age-related increases in attentional demands of walking. We examine whether SWWT is associated with use of explicit movement cues during locomotion, and evaluate if conscious control (i.e., movement specific reinvestment) is causally linked to falls-related anxiety during a complex walking task. We observed whether twenty-four older adults stopped walking when talking when asked a question during an adaptive gait task. After certain trials, participants completed a visual-spatial recall task regarding walkway features, or answered questions about their movements during the walk. In a subsequent experimental condition, participants completed the walking task under conditions of raised postural threat. Compared to a control group, participants who SWWT reported higher scores for aspects of reinvestment relating to conscious motor processing but not movement self-consciousness. The higher scores for conscious motor processing were preserved when scores representing cognitive function were included as a covariate. There were no group differences in measures of general cognitive function, visual spatial working memory or balance confidence. However, the SWWT group reported higher scores on a test of external awareness when walking, indicating allocation of attention away from task-relevant environmental features. Under conditions of increased threat, participants self-reported significantly greater state anxiety and reinvestment and displayed more accurate responses about their movements during the task. SWWT is not associated solely with age-related cognitive decline or generic increases in age-related attentional demands of walking. SWWT may be caused by competition for phonological resources of working memory associated with consciously processing motor actions and appears to be causally linked with fall-related anxiety and increased vigilance.This research was supported by The Royal Society (IE131576) and British Academy (SG132820)

Rare functional missense variants in CACNA1H: what can we learn from Writer's cramp?

Writer's cramp (WC) is a task-specific focal dystonia that occurs selectively in the hand and arm during writing. Previous studies have shown a role for genetics in the pathology of task-specific focal dystonia. However, to date, no causal gene has been reported for task-specific focal dystonia, including WC. In this study, we investigated the genetic background of a large Dutch family with autosomal dominantinherited WC that was negative for mutations in known dystonia genes. Whole exome sequencing identified 4 rare variants of unknown significance that segregated in the family. One candidate gene was selected for follow-up, Calcium Voltage-Gated Channel Subunit Alpha1 H, CACNA1H, due to its links with the known dystonia gene Potassium Channel Tetramerization Domain Containing 17, KCTD17, and with paroxysmal movement disorders. Targeted resequencing of CACNA1H in 82 WC cases identified another rare, putative damaging variant in a familial WC case that did not segregate. Using structural modelling and functional studies in vitro, we show that both the segregating p.Arg481Cys variant and the non-segregating p.Glu1881Lys variant very likely cause structural changes to the Cav3.2 protein and lead to similar gains of function, as seen in an accelerated recovery from inactivation. Both mutant channels are thus available for re-activation earlier, which may lead to an increase in intracellular calcium and increased neuronal excitability. Overall, we conclude that rare functional variants in CACNA1H need to be interpreted very carefully, and additional studies are needed to prove that the p.Arg481Cys variant is the cause of WC in the large Dutch family.Genetics of disease, diagnosis and treatmen

Correction to: Putting genome-wide sequencing in neonates into perspective

The original version of this Article contained an error in the spelling of the author Pleuntje J. van der Sluijs, which was incorrectly given as Eline (P. J.) van der Sluijs. This has now been corrected in both the PDF and HTML versions of the Article

Effects of Anxiety, a Cognitive Secondary Task, and Expertise on Gaze Behavior and Performance in a Far Aiming Task

Objective: Previous studies focused on investigating the separate effects of anxiety, cognitive load, and expertise on perceptual-motor performance, but the combined effects of these factors have not been studied yet. The objective of the current study was to investigate these factors in combination. Design: Eleven expert dart players and nine novices performed a dart throwing task in low-anxiety (LA) and high-anxiety (HA) conditions with and without a secondary task. Method: To manipulate anxiety the dart throwing task was performed low (LA) and high (HA) on a climbing wall with and without the secondary counting backwards task. Performance and efficiency of task execution and gaze behavior were assessed. Results: The anxiety manipulation evoked a decrease in dart performance, but only for the novices. Increases in mental effort and dart times and a decrease in response rate on the secondary task were observed for both groups. This shows that there were decreases in processing efficiency with anxiety. Most important, the anxiety-induced decrease in performance for the novices was accompanied by final fixations on the target that were substantially shorter and deviated off the target earlier. The dual task did not affect performance. Conclusion: Anxiety affects efficiency and sometimes performance in far aiming tasks. Changes are accompanied by changes in gaze behavior, particularly the final fixation on the target. All in all, findings provide support for Attentional Control Theory as a suitable framework to explain the effects of anxiety, a cognitive secondary task, and expertise in far aiming tasks. © 2012 Elsevier Ltd

The effects of anxiety and exercise-induced fatigue on shooting accuracy and cognitive performance in infantry soldiers

Operational performance in military settings involves physical and mental skills that are generally investigated separately in lab settings, leading to reduced ecological validity. Therefore, we investigated the effects of anxiety and exercise-induced fatigue, separately and in combination, on cognitive and shooting performance of 22 soldiers in a real-world setting. Findings indicated that soldiers' shooting accuracy and decision-making and mathematical skills decreased significantly under anxiety. Whether exercise-induced fatigue was beneficial or detrimental to task performance depended on the task at hand. The increased arousal levels through exercise prevented shooting accuracy from deteriorating in the decision task. In contrast, cognitive performance suffered from the increased arousal: participants more often failed to shoot when being fired at by an opponent and also math performance seemed to decrease. We conclude that anxiety can deteriorate soldier performance and that exercise-induced fatigue may improve or deteriorate performance in combination with anxiety depending on the nature of the task. Practitioner Summary: Soldiers encounter anxiety and exercise-induced fatigue. We investigated to what degree these factors influence soldiers' shooting and cognitive performance. Experimental manipulation of anxiety and exercise during a representative field course indicated decreased performance under anxiety. Exercise prevented shooting accuracy from deteriorating under anxiety, although cognitive performance was negatively affected after exercise. © 2014 Taylor & Francis

An app for multidisciplinary sport science: experiences using a modular architecture

For creating sports innovations we need tools to collect data on physical activity behaviour. Collecting data is time-consuming and expensive. Therefore, sharing data and using it to answer multiple research questions is desirable. Especially in larger multidisciplinary research projects, it is beneficial if a diverse data set can be collected effortlessly. For this, we created a smartphone app that can be used for scientific data collection on physical activity behavior in sport research. The requirement for the app was that the different research partners could contribute, use the app independently and that the individual contributions could be easily combined into a larger app. We created a base app which provides a framework for easy implementation of custom modules. Each functionality in the app is represented in a module and can be created by different parties. The app uses the EventBus framework [1] to allow easy communication between independent modules including an independent GUI. In our presentation we will further explain this independance using the beacon physical activity app BAMBEA [4] . Over the span of three years we made a sensor collection-, emotion input-, beacon scanner-, beacon handler-, goal-, reward- and message/notification-module. We combined different modules into different versions. A first version initially focused on running behaviour and used a movement- and a heart rate-module that were originally created for research [2] and different modules of partners (like gait step frequency and emotion detection). The app was extended with a GUI to test the user experience of the modules [3]. Finally, the framework was updated and combined different modules and a new GUI for a bootcamp app [4]. In conclusion we experienced the modular framework as a good solution for reuse and collaboration within multidisciplinary research projects. By allowing for the independent development of modules only intense communication between partners was needed when conflicts occurred between modules. Another advantage was that partners could develop their module in their desired programming language and later integrate their module in the app by providing a small wrapper. We consider the framework approach as a success for projects where close collaboration is desired with a multidisciplinary team. However, we would not advise this approach when it can be expected that multiple heavy performance solutions are required and resources like data collection, storage and backup cannot be shared. In that case a tight integration and continuous collaborative implementation is likely a preferred approach. This research is made possible by the Amsterdam University of Applied Sciences research programs Urban Vitality, Amsterdam Creative Industries Network, the Amsterdam Institute of Sport Sciences (AISS) and by the Dutch National program COMMIT/

Pursue or shoot? Effects of exercise-induced fatigue on the transition from running to rifle shooting in a pursuit task

To investigate to what degree exercise-induced fatigue influences behavioural choices, participants' transition from running to rifle shooting in a pursue-and-shoot task was assessed. Participants ran on a treadmill and chased a target in a virtual environment and were free to choose when to stop the treadmill and shoot at the target. Fatigue increased progressively throughout the 20-minute test. Results indicated that shooting accuracy was not affected by fatigue. However, the distance to the target at which participants decided to shoot showed a U-shaped relationship with fatigue, R2 = 0.884, p = 0.013. At low fatigue levels (ratings of perceived exertion [RPE] 6.5) shooting distance increased again. At high levels of fatigue, participants stopped running sooner, aimed at the target longer and shot less often. Findings indicate that physiological parameters influence not only perception but also actual transitions between different actions. Practitioner Summary: This study was conducted to investigate to what degree exercise-induced fatigue influences behavioural choices. This is an original research article. Our major finding is that physiological parameters influence not only perceptual estimates of action possibilities but also actual behaviours and transitions between different actions. © 2013 Taylor & Francis

De rol van innovatieve technologie in het stimuleren van sport en bewegen in de steden Amsterdam en Eindhoven

De auteurs gaan in dit artikel in op de mogelijkheden van innovatieve technologie in het stimuleren van sport en bewegen en het op maat aanpassen van beweegvriendelijke omgevingen in een stedelijke context. Ze concluderen dat laagdrempelige technologie zoals smartphone applicaties (apps) en wearables veelvuldig worden gebruikt door minder actieve lopers en door vrouwelijke lopers en dat app-gebruikers vaak jonger zijn. De auteurs zien deze mogelijkheden als veelbelovend, maar concluderen ook dat toekomstig onderzoek nodig is om korte- en langetermijneffecten van deze technologie te bevestigen