Isolation and In Vitro Culture of Germ Cells and Sertoli Cells from Human Fetal Testis.

In the human fetal testis, fetal germ cells (FGCs) are progressively surrounded by supporting Sertoli cells inside seminiferous cords. During the second trimester, the FGCs develop asynchronously and can be observed in several stages of development. However, the mechanism that regulates the transition between the different developmental stages as well as the formation of spermatogonia is currently not well understood. For this, it is necessary to develop suitable isolation protocols and a platform for in vitro culture of FGCs of different stages. Here, we report a method to isolate distinct populations of FGCs and Sertoli cells from second trimester human testis using a panel of conjugated antibodies for THY1, PDPN, ALPL, KIT, and SUSD2 for fluorescence-activated cell sorting (FACS) followed by in vitro culture up to 7 days. This platform provides the base for cellular and molecular characterization of the different testicular cell populations to investigate the transition between FGCs and spermatogonia and shed some light on crucial processes of early human gametogenesis unknown until now.

Bilateral Transfer of a Visuomotor Task in Different Workspace Configurations.

Bilateral transfer occurs when a learned behavior transfers from one (group of) effectors(s) to another. Researchers investigating bilateral transfer of a visuomotor adaptation task between limbs used across workspaces have observed divergent results. This study assessed whether bilateral transfer of a visuomotor adaptation task changes with workspace configuration manipulation. Ninety-six right-handed young adults were assigned to one of three workspace locations, i.e., ipsilateral, contralateral, and central. Within each workspace were two retention groups (RRR/LLL) and two bilateral transfer groups (RLR/LRL). Performance before and after training was collected to determine direct and after-effects. We observed an asymmetric transfer of pathlength (left to right) but no ensuing after-effect. However, the transfer of movement time and normalized jerk was symmetric in the contralateral workspace. These findings showed differences in the pattern of bilateral transfer asymmetry in the different workspace configurations, which was parameter specific.

Efficient and scalable generation of primordial germ cells in 2D culture using basement membrane extract overlay.

Current methods to generate human primordial germ cell-like cells (hPGCLCs) from human pluripotent stem cells (hPSCs) can be inefficient, and it is challenging to generate sufficient hPGCLCs to optimize in vitro gametogenesis. We present a differentiation method that uses diluted basement membrane extract (BMEx) and low BMP4 concentration to efficiently induce hPGCLC differentiation in scalable 2D cell culture. We show that BMEx overlay potentiated BMP/SMAD signaling, induced lumenogenesis, and increased expression of key hPGCLC-progenitor markers such as TFAP2A and EOMES. hPGCLCs that were generated using the BMEx overlay method were able to upregulate more mature germ cell markers, such as DAZL and DDX4, in human fetal ovary reconstitution culture. These findings highlight the importance of BMEx during hPGCLC differentiation and demonstrate the potential of the BMEx overlay method to interrogate the formation of PGCs and amnion in humans, as well as to investigate the next steps to achieve in vitro gametogenesis.

Aging reduces manual dexterity and force production asymmetries between the hands.

Age-related effects on motor asymmetry provide insight into changes in cortical activation during aging. To investigate potential changes in manual performance associated with aging, we conducted the Jamar hand function test and the Purdue Pegboard test on young and older adults. All tests indicated reduced motor asymmetry in the older group. Further analysis suggested that a significant decline in dominant (right) hand function resulted in less asymmetric performance in older adults. The finding is inconsistent with the application of the HAROLD model in the motor domain, which assumes improved performance in the non-dominant hand, leading to a reduction of motor asymmetry in older adults. Based on the manual performance in young and older adults, it is suggested that aging reduces manual asymmetry in both force production and manual dexterity due to the reduced performance of the dominant hand.

Attentional focus effects on joint covariation in a reaching task.

Adopting an external focus of attention (EF) has been found beneficial over internal focus (IF) for performing motor skills. Previous studies primarily examined focus of attention (FOA) effects on performance outcomes (such as error and accuracy), with relatively less emphasis on movement coordination. Given that human movements are kinematically and kinetically abundant (Gefland & Latash, 1998), FOA instructions may change how motor abundance is utilized by the CNS. This study applied the uncontrolled manifold analysis (UCM) to address this question in a reaching task. Healthy young adults (N = 38; 22 ± 1 yr; 7 men, 31 women) performed planar reaching movements to a target using either the dominant or nondominant arm under two different FOA instructions: EF and IF. Reaching was performed without online visual feedback and at a preferred pace. Joint angles of the clavicle-scapula, shoulder, elbow, and wrist were recorded, and their covariation for controlling dowel endpoint position was analyzed via UCM. As expected, IF led to a higher mean radial error than EF, driven by increases in aiming bias and variability. Consistent with this result, the UCM analysis showed that IF led to higher goal-relevant variance among the joints (VORT) compared to EF starting from the first 20% of the reach to the end. However, the goal-irrelevant variance (VUCM)-index of joint variance that does not affect the end-effector position-did not show FOA effects. The index of stability of joint coordination with respect to endpoint position (ΔV) was also not different between the EF and IF. Consistent with the constrained action hypothesis, these results provide evidence that IF disrupted goal-relevant joint covariation starting in the early phases of the reach without affecting goal-irrelevant coordination.

A preconception lifestyle intervention in women with obesity and cardiovascular health in their children.

BACKGROUND: Maternal obesity during pregnancy is associated with poorer cardiovascular health (CVH) in children. A strategy to improve CVH in children could be to address preconception maternal obesity by means of a lifestyle intervention. We determined if a preconception lifestyle intervention in women with obesity improved offspring's CVH, assessed by magnetic resonance imaging (MRI). METHODS: We invited children born to women who participated in a randomised controlled trial assessing the effect of a preconception lifestyle intervention in women with obesity. We assessed cardiac structure, function and geometric shape, pulse wave velocity and abdominal fat tissue by MRI. RESULTS: We included 49 of 243 (20.2%) eligible children, 24 girls (49%) girls, mean age 7.1 (0.8) years. Left ventricular ejection fraction was higher in children in the intervention group as compared to children in the control group (63.0% SD 6.18 vs. 58.8% SD 5.77, p = 0.02). Shape analysis showed that intervention was associated with less regional thickening of the interventricular septum and less sphericity. There were no differences in the other outcomes of interest. CONCLUSION: A preconception lifestyle intervention in women with obesity led to a higher ejection fraction and an altered cardiac shape in their offspring, which might suggest a better CVH. IMPACT: A preconception lifestyle intervention in women with obesity results in a higher ejection fraction and an altered cardiac shape that may signify better cardiovascular health (CVH) in their children. This is the first experimental human evidence suggesting an effect of a preconception lifestyle intervention in women with obesity on MRI-derived indicators of CVH in their children. Improving maternal preconception health might prevent some of the detrimental consequences of maternal obesity on CVH in their children.

Differing Impact of Preterm Birth on the Right and Left Atria in Adulthood.

Background Preterm birth affects 10% of live births and is associated with an altered left ventricular and right ventricular phenotype and increased cardiovascular disease risk in young adulthood. Because left atrial (LA) and right atrial (RA) volume and function are known independent predictors of cardiovascular outcomes, we investigated whether these were altered in preterm-born young adults. Methods and Results Preterm-born (n=200) and term-born (n=266) adults aged 18 to 39 years underwent cardiovascular magnetic resonance imaging. LA and RA maximal and minimal volumes (absolute, indexed to body surface area, and as a ratio to ventricular volumes) were obtained to study atrial morphology, while LA and RA stroke volume, strain, and strain rate were used to assess atrial function. Secondary analyses consisted of between-group comparisons based on degree of prematurity. Absolute RA volumes and RA volumes indexed to right ventricular volumes were significantly smaller in preterm-born compared with term-born adults. In addition, RA reservoir and booster strain were higher in preterm-born adults, possibly indicating functional compensation for the smaller RA volumes. LA volumes indexed to left ventricular volumes were significantly greater in preterm-born adults as compared with term-born adults, although absolute LA volumes were similar between groups. LA and RA changes were observed across gestational ages in the preterm group but were greatest in those born very-to-extremely preterm. Conclusions Preterm-born adults show changes in LA and RA structure and function, which may indicate subclinical cardiovascular disease. Further research into underlying mechanisms, opportunities for interventions, and their prognostic value is warranted.

Maternal obesity in pregnancy and children's cardiac function and structure: A systematic review and meta-analysis of evidence from human studies.

The prevalence of obesity is increasing worldwide. Experimental animal studies demonstrate that maternal obesity during pregnancy directly affects cardiac structure and function in their offspring, which could contribute to their increased cardiovascular disease (CVD) risk. Currently, a systematic overview of the available evidence regarding maternal obesity and alterations in cardiac structure and function in human offspring is lacking. We systematically searched the electronic databases Embase, MEDLINE and NARCIS from inception to June 29, 2022 including human studies comparing cardiac structure and function from fetal life onwards in offspring of women with and without obesity. The review protocol was registered with PROSPERO International Prospective Register of Systematic Reviews (identifier: CRD42019125071). Risk of bias was assessed using a modified Newcastle-Ottawa scale. Results were expressed using standardized mean differences (SMD). The search yielded 1589 unique publications, of which thirteen articles were included. Compared to offspring of women without obesity, fetuses of women with obesity had lower left ventricular strain, indicative of reduced systolic function, that persisted in infancy (SMD -2.4, 95% confidence interval (CI) -4.4 standard deviation (SD) to -0.4 SD during fetal life and SMD -1.0, 95% CI -1.6 SD to -0.3 SD in infancy). Furthermore, infants born to women with obesity had a thicker interventricular septum (SMD 0.6 SD, 95% CI 0.0 to 1.2 SD) than children born to women without obesity. In conclusion, cardiac structure and function differs between fetuses and children of women with and without obesity. Some of these differences were present in fetal life, persisted in childhood and are consistent with increased CVD risk. Long-term follow-up research is warranted, as studies in offspring of older age are lacking.

Induction of Bile Canaliculi-Forming Hepatocytes from Human Pluripotent Stem Cells.

Cell polarity and formation of bile canaliculi can be achieved in hepatocytes which are generated from patient-derived induced pluripotent stem cells. This allows for the study of endogenous mutant proteins, patient-specific pathogenesis, and drug responses for diseases where hepatocyte polarity and bile canaliculi play a key role. Here, we describe a step-by-step protocol for the generation of bile canaliculi-forming hepatocytes from induced pluripotent stem cells and their evaluation.

Incompatibility Influences Cursor Placement When Pointing to Images of Cups.

OBJECTIVE: As images are used within graphical user interfaces to signify menu selection, it is important to understand how image properties can influence cursor placement online. BACKGROUND: Objects have multiple dimensions that create potential ambiguity and Stroop-like confusions for the operator if a previously habitual response conflicts with the required response. METHODS: To examine the impact of compatibility and other contextual factors, 41 participants used a computer Mouse or touch screen to place the cursor upon images of full or empty cups that varied in size, and direction of handle. RESULTS: Cursor placements took longer using the Mouse than touch screen. Although participants were placing the cursor on images, the size of the cup, whether it was empty or full, and the handle orientation interacted in their effects upon response duration and cursor placement. The effects of cup size reversed for empty cups or those with incompatible handles. CONCLUSION: Context can influence cursor placement. Perceived spillability influenced precision requirements, and the cup handle can serve as target or a flanking distractor. APPLICATION: Image content can influence screen hotspots. As performance can change with cup spillability, this bodes well for attempts to detect intent from cursor trajectories.

Preconception lifestyle intervention in women with obesity and echocardiographic indices of cardiovascular health in their children.

BACKGROUND: Improving maternal lifestyle before conception may prevent the adverse effects of maternal obesity on their children's future cardiovascular disease (CVD) risk. In the current study, we examined whether a preconception lifestyle intervention in women with obesity could alter echocardiographic indices of cardiovascular health in their children. METHODS: Six years after a randomized controlled trial comparing the effects of a 6-month preconception lifestyle intervention in women with obesity and infertility prior to fertility care to prompt fertility care, 315 of the 341 children conceived within 24 months after randomization were eligible for this study. The intervention was aimed at weight loss (≥5% or until BMI < 29 kg/m2). Children underwent echocardiographic assessment of cardiac structure and function, conducted by a single pediatric cardiologist, blinded to group allocation. Results were adjusted for multiple variables including body surface area, age, and sex in linear regression analyses. RESULTS: Sixty children (32 girls, 53%) were included, mean age 6.5 years (SD 1.09). Twenty-four children (40%) were born to mothers in the intervention group. Children of mothers from the intervention group had a lower end-diastolic interventricular septum thickness (-0.88 Z-score, 95%CI -1.18 to -0.58), a lower left ventricle mass index (-8.56 g/m2, 95%CI -13.09 to -4.03), and higher peak systolic and early diastolic annular velocity of the left ventricle (1.43 cm/s 95%CI 0.65 to 2.20 and 2.39 cm/s 95%CI 0.68 to 4.11, respectively) compared to children of mothers from the control group. CONCLUSIONS: Children of women with obesity, who underwent a preconception lifestyle intervention, had improved cardiac structure and function; a thinner interventricular septum, lower left ventricle mass, and improved systolic and diastolic tissue Doppler velocities. Despite its high attrition rates, our study provides the first experimental human evidence suggesting that preconception lifestyle interventions may present a method of reducing CVD risk in the next generation. CLINICAL TRIAL REGISTRATION: LIFEstyle study: Netherlands Trial Register: NTR1530 ( https://www.trialregister.nl/trial/1461 ). This follow-up study was approved by the medical ethics committee of the University Medical Centre Groningen (METC code: 2008/284).

A three-dimensional atlas of child's cardiac anatomy and the unique morphological alterations associated with obesity.

AIMS: Statistical shape models (SSMs) of cardiac anatomy provide a new approach for analysis of cardiac anatomy. In adults, specific cardiac morphologies associate with cardiovascular risk factors and early disease stages. However, the relationships between morphology and risk factors in children remain unknown. We propose an SSM of the paediatric left ventricle to describe its morphological variability, examine its relationship with biometric parameters and identify adverse anatomical remodelling associated with obesity. METHODS AND RESULTS: This cohort includes 2631 children (age 10.2 ± 0.6 years), mostly Western European (68.3%) with a balanced sex distribution (51.3% girls) from Generation R study. Cardiac magnetic resonance short-axis cine scans were segmented. Three-dimensional left ventricular (LV) meshes are automatically fitted to the segmentations to reconstruct the anatomies. We analyse the relationships between the LV anatomical features and participants' body surface area (BSA), age, and sex, and search for features uniquely related to obesity based on body mass index (BMI). In the SSM, 19 modes described over 90% of the population's LV shape variability. Main modes of variation were related to cardiac size, sphericity, and apical tilting. BSA, age, and sex were mostly correlated with modes describing LV size and sphericity. The modes correlated uniquely with BMI suggested that obese children present with septo-lateral tilting (R2 = 4.0%), compression in the antero-posterior direction (R2 = 3.3%), and decreased eccentricity (R2 = 2.0%). CONCLUSIONS: We describe the variability of the paediatric heart morphology and identify anatomical features related to childhood obesity that could aid in risk stratification. Web service is released to provide access to the new shape parameters.

Single-Cell Transcriptomics Analysis of Human Small Antral Follicles.

Human ovarian folliculogenesis is a highly regulated and complex process. Characterization of follicular cell signatures during this dynamic process is important to understand follicle fate (to grow, become dominant, or undergo atresia). The transcriptional signature of human oocytes and granulosa cells (GCs) in early-growing and ovulatory follicles have been previously described; however, that of oocytes with surrounding GCs in small antral follicles have not been studied yet. Here, we have generated a unique dataset of single-cell transcriptomics (SmartSeq2) consisting of the oocyte with surrounding GCs from several individual (non-dominant) small antral follicles isolated from adult human ovaries. We have identified two main types of (healthy) follicles, with a distinct oocyte and GC signature. Using the CellphoneDB algorithm, we then investigated the bi-directional ligand-receptor interactions regarding the transforming growth factor-ß (TGFß)/bone morphogenetic protein (BMP), wingless-type (MMTV)-integration site (WNT), NOTCH, and receptor tyrosine kinases (RTK) signaling pathways between oocyte and GCs within each antral follicle type. Our work not only revealed the diversity of small antral follicles, but also contributes to fill the gap in mapping the molecular landscape of human folliculogenesis and oogenesis.

Tissue of Origin, but Not XCI State, Influences Germ Cell Differentiation from Human Pluripotent Stem Cells.

Human pluripotent stem cells (hPSCs) are not only a promising tool to investigate differentiation to many cell types, including the germline, but are also a potential source of cells to use for regenerative medicine purposes in the future. However, current in vitro models to generate human primordial germ cell-like cells (hPGCLCs) have revealed high variability regarding differentiation efficiency depending on the hPSC lines used. Here, we investigated whether differences in X chromosome inactivation (XCI) in female hPSCs could contribute to the variability of hPGCLC differentiation efficiency during embryoid body (EB) formation. For this, we first characterized the XCI state in different hPSC lines by investigating the expression of XIST and H3K27me3, followed by differentiation and quantification of hPGCLCs. We observed that the XCI state did not influence the efficiency to differentiate to hPGCLCs; rather, hPSCs derived from cells isolated from urine showed an increased trend towards hPGCLCs differentiation compared to skin-derived hPSCs. In addition, we also characterized the XCI state in the generated hPGCLCs. Interestingly, we observed that independent of the XCI state of the hPSCs used, both hPGCLCs and soma cells in the EBs acquired XIST expression, indicative of an inactive X chromosome. In fact, culture conditions for EB formation seemed to promote XIST expression. Together, our results contribute to understanding how epigenetic properties of hPSCs influence differentiation and to optimize differentiation methods to obtain higher numbers of hPGCLCs, the first step to achieve human in vitro gametogenesis.

Ligand-Receptor Interactions Elucidate Sex-Specific Pathways in the Trajectory From Primordial Germ Cells to Gonia During Human Development.

The human germ cell lineage originates from primordial germ cells (PGCs), which are specified at approximately the third week of development. Our understanding of the signaling pathways that control this event has significantly increased in recent years and that has enabled the generation of PGC-like cells (PGCLCs) from pluripotent stem cells in vitro. However, the signaling pathways that drive the transition of PGCs into gonia (prospermatogonia in males or premeiotic oogonia in females) remain unclear, and we are presently unable to mimic this step in vitro in the absence of gonadal tissue. Therefore, we have analyzed single-cell transcriptomics data of human fetal gonads to map the molecular interactions during the sex-specific transition from PGCs to gonia. The CellPhoneDB algorithm was used to identify significant ligand-receptor interactions between germ cells and their sex-specific neighboring gonadal somatic cells, focusing on four major signaling pathways WNT, NOTCH, TGFß/BMP, and receptor tyrosine kinases (RTK). Subsequently, the expression and intracellular localization of key effectors for these pathways were validated in human fetal gonads by immunostaining. This approach provided a systematic analysis of the signaling environment in developing human gonads and revealed sex-specific signaling pathways during human premeiotic germ cell development. This work serves as a foundation to understand the transition from PGCs to premeiotic oogonia or prospermatogonia and identifies sex-specific signaling pathways that are of interest in the step-by-step reconstitution of human gametogenesis in vitro.

Health care utilization and excess costs after pelvic fractures among older people in Germany.

Our study demonstrates a strong increase in utilization of inpatient health care and clear excess costs in older people in the first year after pelvic fracture, the latter even after adjustment for several confounders. Excess costs were particularly high in the first few months and mainly attributable to inpatient treatment. INTRODUCTION: We aimed to estimate health care utilization and excess costs in patients aged minimum 60 years up to 1 year after pelvic fracture compared to a population without pelvic fracture. METHODS: In this retrospective population-based observational study, we used routine data from a large statutory health insurance (SHI) in Germany. Patients with a first pelvic fracture between 2008 and 2010 (n=5685, 82% female, mean age 80±9 years) were frequency matched with controls (n=193,159) by sex, age at index date, and index month. We estimated health care utilization and mean total direct costs (SHI perspective) with 95% confidence intervals (CIs) using BCA bootstrap procedures for 52 weeks before and after the index date. We calculated cost ratios (CRs) in 4-week intervals after the index date by fitting mixed two-part models including adjustment for possible confounders and repeated measurement. All analyses were further stratified for men/women, in-/outpatient-treated, and major/minor pelvic fractures. RESULTS: Health care utilization and mean costs in the year after the index date were higher for cases than for controls, with inpatient treatment being particularly pronounced. CRs (95% CIs) decreased from 10.7 (10.2-11.1) within the first 4 weeks to 1.3 (1.2-1.4) within week 49-52. Excess costs were higher for inpatient than for outpatient-treated persons (CRs of 13.4 (12.9-13.9) and 2.3 (2.0-2.6) in week 1-4). In the first few months, high excess costs were detected for both persons with major and minor pelvic fracture. CONCLUSION: Pelvic fractures come along with high excess costs and should be considered when planning and allocating health care resources.

Neuroimaging, Behavioral, and Gait Correlates of Fall Profile in Older Adults.

Prior research has suggested that measurements of brain functioning and performance on dual tasks (tasks which require simultaneous performance) are promising candidate predictors of fall risk among older adults. However, no prior study has investigated whether brain function measurements during dual task performance could improve prediction of fall risks and whether the type of subtasks used in the dual task paradigm affects the strength of the association between fall characteristics and dual task performance. In this study, 31 cognitively normal, community-dwelling older adults provided a self-reported fall profile (number of falls and fear of falling), completed a gait dual task (spell a word backward while walking on a GaitRite mat), and completed a supine dual task (rhythmic finger tapping with one hand while completing the AX continuous performance task (AX-CPT) with the other hand) during functional magnetic resonance imaging (fMRI). Gait performance, AX-CPT reaction time and accuracy, finger tapping cadence, and brain functioning in finger-tapping-related and AX-CPT-related brain regions all showed declines in the dual task condition compared to the single task condition. Dual-task gait, AX-CPT and finger tapping performance, and brain functioning were all independent predictors of fall profile. No particular measurement domain stood out as being the most strongly associated measure with fall variables. Fall characteristics are determined by multiple factors; brain functioning, motor task, and cognitive task performance in challenging dual-task conditions all contribute to the risk of falling.

Does Hand-Dominance Matter in Non-Standard Visuomotor Transformations?

Previous nonstandard visuomotor transformation studies using variations of eye-hand coupling and decoupling tasks focused on dominant hand use. The present study expanded this work by including the non-dominant hand. Twenty-four right-hand dominant adults (M = 21 yrs.; 12 females) slid their index finger along a vertical or horizontal touchscreen to move a cursor that was always displayed in the vertical plane. In four different action-perception conditions, the finger and cursor moved either in the same plane and direction or in the other plane and/or opposite direction. Performance differed between the hands only for movement trajectory related variables but not for endpoint related measures. Across conditions the initial direction error was larger when performing with the non-dominant hand (p < 0.001). A significant hand × cursor direction × cursor plane interaction for path length (p < 0.05) revealed longer movement trajectories for the non-dominant hand compared to the dominant hand in conditions with none or one level of eye-hand decoupling, and similar hand performance when movements were made in the horizontal plane with reversed cursor direction, i.e., two eye-hand decoupling levels. Our findings suggest a non-dominant hand overall eye-hand coordination deficit for spatial planning and an inversely related deficit to the eye-hand decoupling level for trajectory execution.

Physical activity modification in youth with congenital heart disease: a comprehensive narrative review.

Congenital heart disease (CHD) affects nearly 1% of births. As survival rates have dramatically improved, the majority of individuals with CHD now live into adulthood. As these patients age, they become prone to a large range of complications, such as chronic heart failure and acquired cardiovascular disease. Promotion of a healthy and active lifestyle from childhood onwards has been suggested as a sustainable and effective strategy to enhance cardiovascular health, improve quality of life and reduce immediate and long-term risk in people with CHD. Well-established physical activity consensus statements for youth with CHD have now been published. In this article, we review how increasing physical activity in youth with CHD may offer immediate and long-term cardiovascular benefits, what is known about physical activity in children with CHD, describe the unique factors that contribute to achieving sufficient and insufficient physical activity levels and summarize the evidence of trials on physical activity promotion in youth with CHD. Furthermore, we discuss some of the challenges that need to be addressed by further research regarding the optimal strategy, timing and format of physical activity intervention programmes in children and adolescents with CHD. IMPACT: Congenital heart disease (CHD) affects nearly 1% of births, with the majority of individuals with CHD now living into adulthood due to improved survival. As CHD patients age, they become prone to a large range of cardiovascular complications. This article discusses how and why increasing physical activity in youth with CHD may offer immediate and long-term cardiovascular benefits, the barriers to achieving sufficient physical activity levels and the evidence from trials on physical activity promotion in youth with CHD. The optimal strategy, timing and format of physical activity intervention programmes in children and adolescents with CHD are discussed.

Motor Deficits in Youth with Concussion History: Issues with Task Novelty or Task Demand?

The present study expands previous work on eye-hand decoupling deficits in youth with concussion history. It examines whether deficits can be linked to difficulties adapting to new task constraints or meeting ongoing task demands. Data from 59 youth with concussion history (M=11 months post-concussion) and 55 no history controls were analyzed. All 114 participants (M=12.5 yrs.) performed two touchscreen-based eye-hand coordination tasks: A standard task with vision and motor action in alignment, and an eye-hand decoupling task with both spatially decoupled, with twenty trials per task condition. First (trial 1-4), middle (trial 9-12), and last (trial 17-20) trial blocks were analyzed in each condition across groups, as well as first and last blocks only. The latter analysis showed in the first block longer response times in the concussion history group in the eye-hand decoupling condition due to a general slowdown of the reaction times across blocks and a trend for higher movement times. Our findings suggest that youth with concussion history have difficulty to adapt to new task constraints associated with complex skill performance during a short series of trials. These results are relevant for athletic trainers, therapists and coaches who work with youth with concussion history.