Atypical development of praxis in children : a neuropsychological approach

Les troubles spécifiques du développement praxique (ou gestuel) sont diagnostiqués comme Dyspraxie ou Trouble de l’Acquisition de la Coordination (TAC). Leur compréhension se heurte à de nombreuses impasses, et dans la définition des concepts de praxies et de coordination motrice et dans l’analyse théorique des déficits qu’ils recouvrent. En l’absence de théorie spécifique à l’enfant, les connaissances concernant le développement atypique des praxies se sont élaborées sur une transposition des modèles « adulte » mais sans en appréhender la pertinence. L’objectif principal ici est de dégager les arguments qui étayeraient l’hypothèse d’un trouble spécifique du développement praxique. Le parti est pris de proposer un examen fondé sur les théories du geste chez l’adulte, et qui cible les différents niveaux cognitifs engagés dans son développement: fonctions perceptives (visuelles, spatiales), exécutives (planification, flexibilité, inhibition) et compréhension orale. Les performances d’enfants diagnostiqués dyspraxiques ou TAC et au développement typique sont comparées dans deux études, de groupes puis de cas multiples. Nos résultats montrent des troubles divers « dans » la production du geste, inconstants dans les profils individuels, et associés avec des déficits non spécifiquement gestuels (perceptifs, exécutifs ou de compréhension). Face à cette hétérogénéité, la thèse propose de déconstruire la conception des troubles spécifiques du développement praxique, au profit d’une analyse qui ne confonde pas un trouble « du » geste avec tout déficit se manifestant « dans » le geste.Specific deficit in praxic (or gestural) development are diagnosed as Dyspraxia or Developmental Coordination Disorder (DCD). Understanding them proves problematic, both when defining the concepts of praxis/motor coordination and when providing a theoretical analysis of the deficits they cover. In the absence of theory specifically related to children, knowledge about atypical development of praxis is gleaned by applying « adult » models, without really understanding whether this is appropriate. The aim of this thesis is to explore the arguments underlying the hypothesis of a specific deficit in praxis development. Tasks were selected based on adult cognitive models of praxis processing in order to enable a comprehensive and theoretically analysis of gestures. We also examined different cognitive functions involved in the praxis development: perception (both visual and spatial), executive functions (planning, flexibility, inhibition) and oral comprehension. The performance of children diagnosed as dyspraxic or DCD is compared to those considered to show typical development in two studies: on groups and multiple case studies. Our results show various difficulties in producing gestures, mostly inconstant in case studies, and related to deficits that are not specifically gestural. Given the heterogeneity of the disorders that we found, this thesis is aimed at deconstructing the concept of specific deficit in praxis development in favour of an analysis that does not confuse gestural problems with other deficits made apparent through gesture

Développement atypique des praxies chez l’enfant : une approche neuropsychologique

Specific deficit in praxic (or gestural) development are diagnosed as Dyspraxia or Developmental Coordination Disorder (DCD). Understanding them proves problematic, both when defining the concepts of praxis/motor coordination and when providing a theoretical analysis of the deficits they cover. In the absence of theory specifically related to children, knowledge about atypical development of praxis is gleaned by applying « adult » models, without really understanding whether this is appropriate. The aim of this thesis is to explore the arguments underlying the hypothesis of a specific deficit in praxis development. Tasks were selected based on adult cognitive models of praxis processing in order to enable a comprehensive and theoretically analysis of gestures. We also examined different cognitive functions involved in the praxis development: perception (both visual and spatial), executive functions (planning, flexibility, inhibition) and oral comprehension. The performance of children diagnosed as dyspraxic or DCD is compared to those considered to show typical development in two studies: on groups and multiple case studies. Our results show various difficulties in producing gestures, mostly inconstant in case studies, and related to deficits that are not specifically gestural. Given the heterogeneity of the disorders that we found, this thesis is aimed at deconstructing the concept of specific deficit in praxis development in favour of an analysis that does not confuse gestural problems with other deficits made apparent through gesture.Les troubles spécifiques du développement praxique (ou gestuel) sont diagnostiqués comme Dyspraxie ou Trouble de l’Acquisition de la Coordination (TAC). Leur compréhension se heurte à de nombreuses impasses, et dans la définition des concepts de praxies et de coordination motrice et dans l’analyse théorique des déficits qu’ils recouvrent. En l’absence de théorie spécifique à l’enfant, les connaissances concernant le développement atypique des praxies se sont élaborées sur une transposition des modèles « adulte » mais sans en appréhender la pertinence. L’objectif principal ici est de dégager les arguments qui étayeraient l’hypothèse d’un trouble spécifique du développement praxique. Le parti est pris de proposer un examen fondé sur les théories du geste chez l’adulte, et qui cible les différents niveaux cognitifs engagés dans son développement: fonctions perceptives (visuelles, spatiales), exécutives (planification, flexibilité, inhibition) et compréhension orale. Les performances d’enfants diagnostiqués dyspraxiques ou TAC et au développement typique sont comparées dans deux études, de groupes puis de cas multiples. Nos résultats montrent des troubles divers « dans » la production du geste, inconstants dans les profils individuels, et associés avec des déficits non spécifiquement gestuels (perceptifs, exécutifs ou de compréhension). Face à cette hétérogénéité, la thèse propose de déconstruire la conception des troubles spécifiques du développement praxique, au profit d’une analyse qui ne confonde pas un trouble « du » geste avec tout déficit se manifestant « dans » le geste

Nature and Specificity of Gestural Disorder in Children with Developmental Coordination Disorder: A Multiple Case Study

Aim: Praxis assessment in children with developmental coordination disorder (DCD) is usually based on tests of adult apraxia, by comparing across types of gestures and input modalities. However, the cognitive models of adult praxis processing are rarely used in a comprehensive and critical interpretation. These models generally involve two systems: a conceptual system and a production system. Heterogeneity of deficits is consistently reported in DCD, involving other cognitive skills such as executive or visual-perceptual and visuospatial functions. Surprisingly, few researches examined the impact of these functions in gestural production. Our study aimed at discussing the nature and specificity of the gestural deficit in DCD using a multiple case study approach.Method: Tasks were selected and adapted from protocols proposed in adult apraxia, in order to enable a comprehensive assessment of gestures. This included conceptual tasks (knowledge about tool functions and actions; recognition of gestures), representational (transitive, intransitive), and non-representational gestures (imitation of meaningless postures). We realized an additional assessment of constructional abilities and other cognitive domains (executive functions, visual-perceptual and visuospatial functions). Data from 27 patients diagnosed with DCD were collected. Neuropsychological profiles were classified using an inferential clinical analysis based on the modified t-test, by comparison with 100 typically developing children divided into five age groups (from 7 to 13 years old).Results: Among the 27 DCD patients, we first classified profiles that are characterized by impairment in tasks assessing perceptual visual or visuospatial skills (n = 8). Patients with a weakness in executive functions (n = 6) were then identified, followed by those with an impaired performance in conceptual knowledge tasks (n = 4). Among the nine remaining patients, six could be classified as having a visual spatial/visual constructional dyspraxia. Gestural production deficits were variable between and within profiles.Discussion: This study confirmed the heterogeneity of gestural production deficit among children with a diagnosis of DCD, at both intra- and inter-individual levels. The contribution of other cognitive deficits in most of the profiles allows discussing the specificity of gestural difficulties. This argues in favor of the necessity to distinguish gestural problems with other deficits made apparent through gesture

Involvement of Technical Reasoning more than Functional Knowledge in development of tool use in childhood

It is well-known that even toddlers are able to manipulate tools in an appropriate manner according to their physical properties. The ability of children to make novel tools in order to solve problems is, however, surprisingly limited. In adults, mechanical problem solving has been proposed to be supported by technical reasoning skills, which are thought to be involved in every situation requiring the use of a tool (whether conventional or unusual). The aim of this study was to investigate the typical development of real tool use skills and its link with technical reasoning abilities in healthy children. Three experimental tasks were adapted from those used with adults: mechanical problem solving (three different apparatus), real tool use (10 familiar tool-object pairs), and functional knowledge (10 functional picture matching with familiar tools previously used). The tasks were administered to 85 healthy children divided into six age groups (from 6 to 14 years of age). The results revealed that real tool use (p = .01) and mechanical problem solving skills improve with age, even if this improvement differs according to the apparatus for the latter (p < .01 for the Hook task and p < .05 for the Sloping task). Results also showed that mechanical problem solving is a better predictor of real tool use than functional knowledge, with a significant and greater weight (importance weight: 0.65; Estimate±Standard Error: 0.27±0.08). Ours findings suggest that real tool use and technical reasoning develop jointly in children, independently from development of functional knowledge. In addition, technical reasoning appears partially operative from the age of 6 onwards, even though the outcome of these skills depends of the context in which they are applied (i.e., the type of apparatus)

L’utilisation d’outils chez l’enfant : approche épistémologique et sémiologie clinique dans le trouble développemental de la coordination

International audienceTool use disorders are frequently reported in clinical pediatrics, specifically in the case of developmental coordination disorder (DCD). They can reduce children’s participation in day-to-day activities. However, operational strategies for assessment are unorganized and do not consistently consider the impact of impairments on daily life, due to the lack of a consensual explanatory theory in DCD. In this paper, we firstly examine the nature of gestural and motor coordination disorders in children with DCD, as well as their possible role in tool use. The relevance of theoretical concepts and clinical assessment used are also examined with regard to the analysis of tool use impairment. Second, we outline theoretical frameworks in typical development and in adult neuropsychology, which would shed light on the understanding of these symptoms in children with DCD. Finally, we discuss the clinical perspectives for a differential and theoretical assessment of tool use in children.Les troubles d’utilisation d’outils constituent une plainte fréquente en clinique pédiatrique, notamment en cas de trouble développemental de la coordination (TDC), et peuvent limiter la participation de l’enfant aux activités de vie quotidienne. Pourtant, l’absence de théorie explicative consensuelle dans le TDC induit des stratégies d’examen peu structurées, voire affranchies de cadrage théorique, qui n’intègrent pas automatiquement l’évaluation du retentissement des difficultés dans la vie quotidienne. Cet article propose d’interroger, dans une première partie, la nature des troubles gestuels et de coordination motrice chez l’enfant TDC ainsi que leur rôle éventuel dans l’utilisation d’outils. La pertinence des concepts théoriques et des évaluations cliniques mises en œuvre est également questionnée au regard de l’analyse des difficultés d’utilisation. La seconde partie expose les modélisations théoriques formulées dans le développement typique et en neuropsychologie adulte, susceptibles d’éclairer la compréhension de ces symptômes chez l’enfant TDC. Enfin, les perspectives d’un examen différentiel et théoriquement guidé de l’utilisation d’outils chez l’enfant sont abordées à l’issue de cette revue

Praxis skills and executive function in children with neurofibromatosis type 1

International audienceThis study aimed at examining motor and ideomotor praxis skills in children with neurofibromatosis type 1 (NF1). The impact of executive dysfunction, frequently described in children with NF1, on the expression of praxis impairments was also studied. Eighteen children with NF1 were included and matched with 20 control children for age (7–14 years), sex, laterality, and parental education level. Both groups of children underwent an assessment based on cognitive models of apraxia including visuomotor tasks, executive tests, and everyday life questionnaires. The group of children with NF1 showed a trend to weaker performances on motor and ideomotor praxis than the control group, only on the finger use condition (ps  .08). Moreover, these praxis difficulties disappeared when executive dysfunctions (planning and inhibition) were controlled. These findings support the negative impact of executive dysfunctions on praxis skills in children with NF1. The identification of praxis and executive function disorders as well as their interaction is important for differentiating primary praxic disorder from a cognitive deficit that may be expressed in gesture. Clinically, this distinction is essential to optimize targeted and effective rehabilitative interventions

Nature and Specificity of Gestural Disorder in Children with Developmental Coordination Disorder: A Multiple Case Study

International audiencePraxis assessment in children with developmental coordination disorder (DCD) is usually based on tests of adult apraxia, by comparing across types of gestures and input modalities. However, the cognitive models of adult praxis processing are rarely used in a comprehensive and critical interpretation. These models generally involve two systems: a conceptual system and a production system. Heterogeneity of deficits is consistently reported in DCD, involving other cognitive skills such as executive or visual-perceptual and visuospatial functions. Surprisingly, few researches examined the impact of these functions in gestural production. Our study aimed at discussing the nature and specificity of the gestural deficit in DCD using a multiple case study approach. Method: Tasks were selected and adapted from protocols proposed in adult apraxia, in order to enable a comprehensive assessment of gestures. This included conceptual tasks (knowledge about tool functions and actions; recognition of gestures), representational (transitive, intransitive), and non-representational gestures (imitation of meaningless postures). We realised an additional assessment of constructional abilities and other cognitive domains (executive functions, visual-perceptual and visuospatial functions). Data from 27 patients diagnosed with DCD were collected. Neuropsychological profiles were classified using an inferential clinical analysis based on the modified t-test, by comparison with 100 typically developing children divided into five age groups (from 7 to 13 years old). Results: Among the 27 DCD patients, we first classified profiles that are characterised by impairment in tasks assessing perceptual visual or visuospatial skills (n = 8). Patients with a weakness in executive functions (n = 6) were then identified, followed by those with an impaired performance in conceptual knowledge tasks (n = 4). Among the 9 remaining patients, 6 could be classified as having a visual spatial/visual constructional dyspraxia. Gestural production deficits were variable between and within profiles. Discussion: This study confirmed the heterogeneity of gestural production deficit among children with a diagnosis of DCD, at both intra- and inter-individual levels. The contribution of other cognitive deficits in most of the profiles allows discussing the specificity of gestural difficulties. This argues in favour of the necessity to distinguish gestural problems with other deficits made apparent through gesture

Involvement of Technical Reasoning More Than Functional Knowledge in Development of Tool Use in Childhood

International audienceIt is well-known that even toddlers are able to manipulate tools in an appropriate manner according to their physical properties. The ability of children to make novel tools in order to solve problems is, however, surprisingly limited. In adults, mechanical problem solving (MPS) has been proposed to be supported by "technical reasoning skills," which are thought to be involved in every situation requiring the use of a tool (whether conventional or unusual). The aim of this study was to investigate the typical development of real tool use (RTU) skills and its link with technical reasoning abilities in healthy children. Three experimental tasks were adapted from those used with adults: MPS (three different apparatus), RTU (10 familiar tool-object pairs), and functional knowledge (FK; 10 functional picture matching with familiar tools previously used). The tasks were administered to 85 healthy children divided into six age groups (from 6 to 14 years of age). The results revealed that RTU ( = 0.01) and MPS skills improve with age, even if this improvement differs according to the apparatus for the latter ( &lt; 0.01 for the Hook task and &lt; 0.05 for the Sloping task). Results also showed that MPS is a better predictor of RTU than FK, with a significant and greater weight (importance weight: 0.65; Estimate ± Standard Error: 0.27 ± 0.08). Ours findings suggest that RTU and technical reasoning develop jointly in children, independently from development of FK. In addition, technical reasoning appears partially operative from the age of six onward, even though the outcome of these skills depends of the context in which they are applied (i.e., the type of apparatus)

Utilisation d'objets chez l'enfant TDC : Altération spécifique du système de production gestuelle ?

Peu d’études s’intéressant au Trouble Développemental de la Coordination (TDC) chez l’enfant examinent l’impact de ce trouble d’apprentissage sur les activités de vie quotidienne [1] et l’utilisation réelle d’objets, alors même que les plaintes décrites par l’entourage des enfants se cristallisent à ce niveau (e.g., utilisation des couverts, habillage, graphisme...). Cette étude a pour objectif d’évaluer les difficultés d’utilisation effective d’objets chez les enfants TDC et d’appréhender les processus cognitivo moteurs impliqués : l’anticipation motrice, la dextérité manuelle, ou encore le raisonnement technique et les connaissances sémantiques [2].Méthode : Vingt-trois enfants diagnostiqués TDC d’après les critères du DSM-5 [3] ont été appariés avec 44 enfants ne présentant pas de trouble d’apprentissage, au niveau de l’âge (7-13 ans), du genre, du niveau socioculturel parental et de la latéralité. Le protocole expérimental comprenait des épreuves de sélection et d’utilisation d’objets familiers (utilisation réelle), de résolution de problèmes mécaniques (raisonnement technique), d’appariement d’images d’objets selon leur fonction (connaissances sémantiques), de saisie et de transport de bâton (anticipation motrice) et d’insertion de petites tiges dans une planche (dextérité manuelle). Résultats : Des difficultés d’utilisation effective d’objets sont relevées chez le groupe TDC (p &lt; .0001), ainsi qu’une altération des capacités d’anticipation motrice (p &lt; .01) et de dextérité manuelle (p &lt; .0001). En revanche, les performances de résolution de problèmes mécaniques et d’appariement fonctionnel d’images étaient comparables chez les enfants TDC et chez les enfants tout-venant. Discussion : Nos résultats confirment de manière innovante l’existence de difficultés d’utilisation effective d’objets chez les enfants TDC, ainsi que de fortes associations avec le déficit de dextérité manuelle. L’hypothèse explicative d’une perturbation de simulation motrice affectant l’utilisation réelle d’objets est discutée en comparaison de celle d’un déficit d’exécution motrice

Gestures and related skills in developmental coordination disorder: a production-system deficit?

International audienceThe present study investigated the nature and specificity of the gestural deficit in children with developmental coordination disorder (DCD). Performance of children with DCD is compared with that of typically developing children across tasks and conditions that allow exploring distinct levels hypothesized by adult models of praxis processing. These models generally involve a conceptual system and a production system. Within this theoretical framework, the study analyzed the extent to which the gestural difficulties of children with DCD are related to a deficit of the production system. Considering the heterogeneity of deficits consistently reported in DCD, we also examined whether gestural difficulties of children with DCD could imply impairments on other cognitive functions (executive functions, visual-perceptual, and visuospatial functions). Thirty children with DCD were compared to 30 typically developing children. The DCD group exhibited a deficit in most of the gesture production tasks (with the exception of representational intransitive ones), with impaired visuospatial skills. When controlling for a measure of visuospatial skill, differences between groups remained significant only for representational transitive gestures. This dysfunction could neither be related to a semantic deficit, nor to an impairment of sensorimotor knowledge. Therefore, if the contribution of a visuospatial dysfunction allows discussing the specificity of gestural deficit, this does not appear to explain the overall gestural deficit. We suggest an explanation of the finding within the assumption of a production-system deficit