124 research outputs found

    Internal Languages of Finitely Complete (,1)(\infty, 1)-categories

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    We prove that the homotopy theory of Joyal's tribes is equivalent to that of fibration categories. As a consequence, we deduce a variant of the conjecture asserting that Martin-L\"of Type Theory with dependent sums and intensional identity types is the internal language of (,1)(\infty, 1)-categories with finite limits.Comment: 41 pages, minor revision

    The impact of brain lesion characteristics and the corticospinal tract wiring on mirror movements in unilateral cerebral palsy.

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    Mirror movements (MM) influence bimanual performance in children with unilateral cerebral palsy (uCP). Whilst MM are related to brain lesion characteristics and the corticospinal tract (CST) wiring pattern, the combined impact of these neurological factors remains unknown. Forty-nine children with uCP (mean age 10y6mo) performed a repetitive squeezing task to quantify similarity (MM-similarity) and strength (MM-intensity) of the MM activity. We used MRI data to evaluate lesion type (periventricular white matter, N = 30; cortico-subcortical, N = 19), extent of ipsilesional damage, presence of bilateral lesions, and damage to basal ganglia, thalamus and corpus callosum. The CST wiring was assessed with Transcranial Magnetic Stimulation (17 CSTcontralateral, 16 CSTipsilateral, 16 CSTbilateral). Data was analyzed with regression analyses. In the more-affected hand, MM-similarity and intensity were higher with CSTbilateral/ipsilateral. In the less-affected hand, MM-similarity was higher in children with (1) CSTcontra with CSC lesions, (2) CSTbilat/ipsi with PVL lesions and (3) CSTbilat/ipsi with unilateralized lesions. MM-intensity was higher with larger damage to the corpus callosum and unilateral lesions. A complex combination of neurological factors influences MM characteristics, and the mechanisms differ between hands

    Action observation training for rehabilitation in brain injuries: A systematic review and meta-analysis

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    Background : To systematically review and analyse the effects of Action Observation Training on adults and children with brain damage. Methods : Seven electronic databases (Cochrane, EBSCO, Embase, Eric, PubMed, Scopus and Web of Science) were searched up to 16 September 2018 to select Randomized Controlled Trials focused on adults and children with brain damage that included AOT training on upper and/or lower limb carried out for at least 1 week. Identification of studies and data extraction was conducted with two reviewers working independently. Oxford Centre for Evidence-based Medicine (March2009) – Levels of Evidence and Physiotherapy Evidence Database scale were used to grade studies. The data collected from the articles were analysed using software R, version 3.4.3. Hedge’s g values were calculated and effect size estimates were pooled across studies. Separate meta-analyses were carried out for each ICF domain (i.e. body function and activity) for upper and lower limb. Results : Out of the 210 records identified after removing duplicates, 22 were selected for systematic review and 19 were included in the meta-analysis. Thirteen studies included in the meta-analysis focused on upper limb rehabilitation (4 in children and 9 in adults) and 6 on lower limb rehabilitation (only studies in adults). A total of 626 patients were included in the meta-analysis. An overall statistically significant effect size was found for upper limb body function (0.44, 95% CI: [0.24, 0.64], p<0.001) and upper limb activity domain (0.47, 95% CI: [0.30, 0.64], p<0.001). For lower limb, only the activity domain was analysed, revealing a statistically significant overall effect size (0.56, 95% CI: [0.28, 0.84], p<0.001). Conclusions : Action Observation Training (AOT) is an innovative rehabilitation tool for individuals with brain damage, which shows promising results in improving the activity domain for upper and lower limbs, and also the body function domain for the upper limb. However, the examined studies lack uniformity and further well-designed, larger controlled trials are necessary to determine the most suitable type of AOT particularly in childre

    Validity and cross-cultural differences of the Bayley Scales of Infant and Toddler Development, Third Edition in typically developing infants

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    BACKGROUND: The Dutch translation of Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III-NL) is a comprehensive tool assessing cognitive, language and motor development in children up to 42 months. AIMS: The first aim of this study was to evaluate concurrent validity of the Bayley-III-NL Gross Motor Scale (GMS) in relation to the Alberta Infant Motor Scale (AIMS). Secondly, divergent validity between the other subscales mutually and the AIMS was investigated. Finally, the importance of population-specific reference values was examined. METHODS AND PROCEDURES: A sample of 122 healthy, typically developing Flemish children (mean age: 9 months 7 days), born full term was assessed with the Bayley-III-NL and the AIMS. OUTCOMES AND RESULTS: Concurrent validity of the Bayley-III-NL GMS and the AIMS was moderate to high (0.59-0.98; p < 0.001). In addition, weak correlations (-0.10-0.27) between the non-motor-Bayley-III-NL subscales and the AIMS were found. Finally, significant differences were found between Bayley-III scores based on Flemish and American norms (p < 0.001), except for fine motor skills (p = 0.11). CONCLUSIONS AND IMPLICATIONS: This study provides support for the concurrent validity of the Bayley-III-NL GMS and divergent validity of the different Bayley-III-NL subscales. Secondly, population-specific reference values should be used to avoid over- and under estimation of infant's development.status: publishe

    BRIDGING THE GAP BETWEEN NEUROSCIENCE AND CLINICAL RESEARCH IN UNILATERAL CEREBRAL PALSY

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    Purpose: To bridge the gap between neuroscience and clinical research in unilateral CP and discuss the added value of understanding the reorganisation of the brain in these children, based on mirror movements and neuroimaging, and how this knowledge can contribute to treatment optimisation. Target Audience: occupational therapists, physiotherapists, paediatric neurologists Course Summary: Children with unilateral cerebral palsy (CP) are characterised by a large heterogeneity in upper limb function and treatment response. Due to the early nature of the brain lesion, these children present with a unique “re-wiring” of the sensorimotor system, i.e. the corticospinal tract (CST). Structural reorganisation of the CST has been proposed to play a crucial role in the clinical heterogeneity and might offer a valuable therapeutic target. However, the CST-wiring pattern is not immediately apparent from the child’s clinical presentation. During this course, we will provide a concise overview of the role of mirror movements in typically developing children and unilateral CP (Prof. Dr. K. Klingels). Next, we will discuss various ways to probe the motor system and identify the CST-wiring pattern in these children, based on transcranial magnetic stimulation, a quantitative mirror movement assessment, and different neuroimaging techniques including diffusion imaging and resting state fMRI (Dr. E. Jaspers, MSc C. Simon-Martinez). Finally, most recent work will be presented on the added value of non-invasive brain stimulation to improve upper limb function in children with unilateral CP (Prof. Dr. med. A. Kirton). Learning Objectives: 1. Understand the role of mirror movements in typically developing children and unilateral cerebral palsy 2. Describe different ways of probing the motor system, based on behavioral, neurophysiological and neuroimaging assessments 3. Understand how the different behavioral, neurophysiological and neuroimaging assessments can be implemented in clinical practice 4. Understand the added value of non-invasive brain stimulation in upper limb rehabilitationstatus: publishe

    Negative Influence of Motor Impairments on Upper Limb Movement Patterns in Children with Unilateral Cerebral Palsy. A Statistical Parametric Mapping Study

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    Upper limb three-dimensional movement analysis (UL-3DMA) offers a reliable and valid tool to evaluate movement patterns in children with unilateral cerebral palsy (uCP). However, it remains unknown to what extent the underlying motor impairments explain deviant movement patterns. Such understanding is key to develop efficient rehabilitation programs. Although UL-3DMA has been shown to be a useful tool to assess movement patterns, it results in a multitude of data, challenging the clinical interpretation and consequently its implementation. UL-3DMA reports are often reduced to summary metrics, such as average or peak values per joint. However, these metrics do not take into account the continuous nature of the data or the interdependency between UL joints, and do not provide phase-specific information of the movement pattern. Moreover, summary metrics may not be sensitive enough to estimate the impact of motor impairments. Recently, Statistical Parametric Mapping (SPM) was proposed to overcome these problems. We collected UL-3DMA of 60 children with uCP and 60 typically developing children during eight functional tasks and evaluated the impact of spasticity and muscle weakness on UL movement patterns. SPM vector field analysis was used to analyze movement patterns at the level of five joints (wrist, elbow, shoulder, scapula, and trunk). Children with uCP showed deviant movement patterns in all joints during a large percentage of the movement cycle. Spasticity and muscle weakness negatively impacted on UL movement patterns during all tasks, which resulted in increased wrist flexion, elbow pronation and flexion, increased shoulder external rotation, decreased shoulder elevation with a preference for movement in the frontal plane and increased trunk internal rotation. Scapular position was altered during movement initiation, although scapular movements were not affected by muscle weakness or spasticity. In conclusion, we identified pathological movement patterns in children with uCP and additionally mapped the negative impact of spasticity and muscle weakness on these movement patterns, providing useful insights that will contribute to treatment planning. Last, we also identified a subset of the most relevant tasks for studying UL movements in children with uCP, which will facilitate the interpretation of UL-3DMA data and undoubtedly contribute to its clinical implementation

    Reliability and concurrent validity of a modified timed up and go test for healthy preschoolers

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    The purpose of this study was to assess the interrater and test-retest reliability and the concurrent validity of the modified timed up and go test for preschoolers. As such, we aim to determine the most suited outcome of the modified timed up and go test: the best or the average performance. Thirty-two children (age 3-5) performed three timed up and go test trials as fast as possible on two separate occasions. During the first session, two researchers recorded the time to perform the task simultaneously. For reliability analyses, intra-class correlation coefficients (ICCs) and the minimal detectable change were determined. A Pearson correlation coefficient was calculated to determine concurrent validity between the timed up and go test and the balance subscale of the Movement Assessment Battery for Children, 2nd edition. Interrater (ICC > 0.97) and test-retest (ICC > 0.75) reliability were good both for the average and the best timed up and go test performance. A minimal detectable change of 1.86 s was found for the best performance, and 2.30 s for the average performance. Only the best timed up and go test performance correlated significantly with the balance subscale of the Movement Assessment Battery for Children, 2nd edition, though fair (r = -0.347, p = 0.007).Conclusion: The modified timed up and go test for preschoolers using the best performance is reliable and recommended to reduce standard and measurement error. What is Known: • A large variety of timed up and go test protocols is available for children • The protocols differ in the instructions on walking speed (self-selected/fastest), the use of an extra motivation (e.g., touch a star on the wall) and the applied outcome (average/best performance) What is New: • The best timed up and go test performance induces more consistent test results between raters and sessions and also less standard and measurement error in 3- to 5-year-old children • The best timed up and go test performance should be preferred over the average performance to achieve both reliable and valid test results in 3- to 5-year-old children.status: publishe
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