Movement Control Strategies in a Dynamic Balance Task in Children With and Without Developmental Coordination Disorder

Our study aimed to analyze movement control strategies using predefined criteria for amplitude and differences in these strategies between children with and without DCD. Children with (n = 28) and without DCD (n = 15) were included. A video-observation-tool was used to score the moving body parts during a Wii Fit slalom task over multiple time points. Two-step cluster analysis was used to extract distinct movement strategies. Two different movement strategies were identified that were independently validated by a measure of task performance and a subjective mark of quality of the movement. Initial differences between groups and changes over time toward the more successful strategy were found in both groups, albeit in a different percentage. This study shows that the more efficient movement strategy is seen in the majority of the TD children and only in a small number of children with DCD, even after practice

An examination of the influence of prenatal sex hormones on handedness: Literature review and amniotic fluid data

Competing theories have posited roles for foetal androgen exposure in the development of human handedness. However, due to practical and ethical considerations, few studies have used hormonal measures to examine this possibility. The current paper reviews this literature and reveals a generally inconsistent pattern of results. We also present data from a longitudinal study of prenatal sex hormone exposure and subsequent handedness. More specifically, we examine correlations between testosterone and estradiol measured from second trimester amniotic fluid and hand preference (Dutch language version of the Edinburgh Handedness Inventory) and hand skill asymmetry (pegboard task) measured at 15 years of age. Prenatal sex hormone exposure was not associated with the direction of hand preference in either males or females. However, in females, high levels of prenatal testosterone were associated with weaker lateralisation of hand skill, and high levels of prenatal estradiol were associated with weaker hand preference. In addition, high levels of prenatal testosterone were associated with increased task duration (i.e., slow hand speed) for the right and left hands of males. The pattern of results observed here is not entirely consistent with any of the main theories linking sex hormones with handedness, suggesting that an association between these variables may be more complex than initially thought

Effect of dual tasking on a dynamic balance task in children with and without DCD

The purpose of this study was to compare performance of children with Developmental Coordination Disorder (DCD) and typically developing (TD) children in a dual task paradigm with a dynamic balance task on the Wii Fit as primary task and a concurrent cognitive (counting) or a concurrent bimanual fine motor task as secondary tasks. Using a cross-sectional design, 25 children with DCD and 38 TD children were assessed with the Movement Assessment Battery for Children, 2nd edition (MABC-2) and Divided Attention (DA) task of the KiTAP. Next, the single- and dual-tasks were performed and the level of interference or facilitation of the dual tasks was calculated. Regression analysis determined the predictive value of the DA and MABC-2 component balance outcomes on the dual task performance. On the motor and attentional tasks, the group of children with DCD scored significantly below the level of the TD children. The dual task effect showed similar interference and facilitation of tasks in the different dual-task conditions in both groups. In the dual task-cognitive condition, the divided attention abilities and the MABC-2 balance score predicted 25% of the Wii Fit dynamic balance task performance, whereas in the dual task-motor condition this was higher (31.6%). In both conditions, DA was a stronger predictor than MABC balance score and appears to be an important factor to consider when developing motor task training for children with DCD.</p

Prenatal and pubertal testosterone affect brain lateralization

After decades of research, the influence of prenatal testosterone on brain lateralization is still elusive, whereas the influence of pubertal testosterone on functional brain lateralization has not been investigated, although there is increasing evidence that testosterone affects the brain in puberty. We performed a longitudinal study, investigating the relationship between prenatal testosterone concentrations in amniotic fluid, pubertal testosterone concentrations in saliva, and brain lateralization (measured with functional Transcranial Doppler ultrasonography (fTCD)) of the Mental Rotation, Chimeric Faces and Word Generation tasks. Thirty boys and 30 girls participated in this study at the age of 15 years. For boys, we found a significant interaction effect between prenatal and pubertal testosterone on lateralization of Mental Rotation and Chimeric Faces. In the boys with low prenatal testosterone levels, pubertal testosterone was positively related to the strength of lateralization in the right hemisphere, while in the boys with high prenatal testosterone levels, pubertal testosterone was negatively related to the strength of lateralization. For Word Generation, pubertal testosterone was negatively related to the strength of lateralization in the left hemisphere in boys. For girls, we did not find any significant effects, possibly because their pubertal testosterone levels were in many cases below quantification limit. To conclude, prenatal and pubertal testosterone affect lateralization in a task-specific way. Our findings cannot be explained by simple models of prenatal testosterone affecting brain lateralization in a similar way for all tasks. We discuss alternative models involving age dependent effects of testosterone, with a role for androgen receptor distribution and efficiency

Pre-trauma memory contextualization as predictor for PTSD-like behavior in male rats

While many people experience potentially threatening events during their life, only a minority develops posttraumatic stress disorder (PTSD). The identification of individuals at risk among those exposed to trauma is crucial for PTSD prevention in the future. Since re-experiencing trauma elements outside of the original trauma-context is a core feature of PTSD, we investigate if the ability to bind memories to their original encoding context (i.e. memory contextualization) predicts PTSD vulnerability. We hypothesize that pre-trauma neutral memory contextualization (under stress) negatively relates to PTSD-like behavior, in a prospective design using the cut-off behavioral criteria rat model for PTSD. 72 male Sprague Dawley rats were divided in two experimental groups to assess the predictive value of 1) memory contextualization without acute stress (NS-group) and 2) memory contextualization during the recovery phase of the acute stress-response (S-group) for susceptibility to PTSD-like behavior. A powerful extension to regression analysis -path analysis-was used to test this specific hypothesis, together with secondary research questions. Following traumatic predator scent stress, 19.4% of the rats displayed PTSD-like behavior. Results showed a negative relation between pre-trauma memory contextualization and PTSD-like behavior, but only in the NS-group. Pre-trauma memory contextualization was positively related to fear association in the trauma environment, again only in the NS group. If the predictive value of pre-trauma contextualization of neutral information under non-stressful conditions for PTSD susceptibility is replicated in prospective studies in humans, this factor would supplement already known vulnerability factors for PTSD and improve the identification of individuals at risk among the trauma exposed, especially those at high trauma risk such as soldiers deployed on a mission

Barriers and facilitators for treatment-seeking for mental health conditions and substance misuse:Multi-perspective focus group study within the military

Background Globally, millions are exposed to stressors at work that increase their vulnerability to develop mental health conditions and substance misuse (such as soldiers, policemen, doctors). However, these types of professionals especially are expected to be strong and healthy, and this contrast may worsen their treatment gap. Although the treatment gap in the military has been studied before, perspectives of different stakeholders involved have largely been ignored, even though they play an important role. Aims To study the barriers and facilitators for treatment-seeking in the military, from three different perspectives. Method In total, 46 people participated, divided into eight homogeneous focus groups, including three perspectives: soldiers with mental health conditions and substance misuse (n = 20), soldiers without mental health conditions and substance misuse (n = 10) and mental health professionals (n = 16). Sessions were audio-taped and transcribed verbatim. Content analysis was done by applying a general inductive approach using ATLAS.ti-8.4.4 software. Results Five barriers for treatment-seeking were identified: fear of negative career consequences, fear of social rejection, confidentiality concerns, the ‘strong worker’ workplace culture and practical barriers. Three facilitators were identified: social support, accessibility and knowledge, and healthcare within the military. The views of the different stakeholder groups were highly congruent. Conclusions Barriers for treatment-seeking were mostly stigma related (fear of career consequences, fear of social rejection and the ‘strong worker’ workplace culture) and this was widely recognised by all groups. Social support from family, peers, supervisors and professionals were identified as important facilitators. A decrease in the treatment gap for mental health conditions and substance misuse is needed and these findings provide direction for future research and destigmatising interventions