L’objectif de cette thèse était de mettre en évidence les différentes stratégies adaptatives posturales et motrices face à une contrainte temporelle chez le jeune adulte et la personne âgée lors de la production d’un mouvement complexe mobilisant l’ensemble du corps. Le modèle de mouvement choisi est composé d’une flexion rapide de la cuisse dominante associée à une extension simultanée de l’index ipsilatéral. Les résultats de la première étude ont montré que le mode de déclenchement de la commande motrice modifiait l’organisation posturale du mouvement. La durée des APA associés à la flexion de la cuisse était plus courte en condition de pression temporelle forte (condition temps de réaction, TR) qu’en condition de pression temporelle faible (condition auto-initiée, AI). Cette diminution de la durée des APA était compensée par une augmentation du pic de déplacement anticipateur du centre des pressions (CP) vers la jambe oscillante. De cette façon, la stabilité dynamique ainsi que la performance motrice restaient inchangées. Les résultats de la deuxième étude ont montré que les sujets âgés étaient également capables de réduire la durée des APA en condition TR. Cependant, au contraire des sujets jeunes, ils ne compensaient pas cette diminution par une augmentation du déplacement anticipé du CP. La stabilité dynamique au moment du décollement du pied était dégradée dans cette population. Par ailleurs, l’effet de la pression temporelle sur la synchronisation motrice ne changeait pas avec l’avancée en âge. Cependant, l’erreur de synchronisation était plus importante chez les âgés que chez les jeunes, en condition AI uniquement. Enfin, l’étude 3 a montré que la modification transitoire des propriétés mécaniques des membres inférieurs (par l’addition d’une charge de 5 kg aux chevilles) affectait l’ordre de synchronisation du mouvement, en condition TR uniquement. En présence d’une charge, les sujets semblent basculer d’un mode de synchronisation de type « réactif » vers un mode « prédictif », ce qui leur permettait de maintenir une précision de synchronisation optimale. En revanche, le mode de contrôle des APA ne changeait pas. Il semble donc que le mode de contrôle des APA et de la synchronisation des mouvements puissent être dissociés selon les contraintes biomécaniques imposées par l’expérimentation. L’ensemble de ces résultats met en évidence la capacité du SNC à moduler l’ordre temporel de la synchronisation du mouvement ainsi que les paramètres spatio-temporels des APA dans le but d’assurer une coordination temporelle et une stabilité dynamique optimales. / This work aimed to investigate the adaptive postural and motor strategies developed by young and elderly healthy subjects during a complex task involving the whole body when facing a temporal pressure constraint. The motor task chosen was a simultaneous rapid leg flexion paired with ipsilateral finger index extension. Results of the first study showed that the mode of triggering of movement modifies the postural organization of the leg flexion. The APA duration associated with leg flexion was shorter in the reaction-time (RT, high temporal pressure) condition as compared to the self-initiated (SI, low temporal pressure) condition. This APA shortening was compensated by an increase of APA amplitude so that the mediolateral (ML) stability and the motor performance were both unchanged. Results of the second study showed that elderly subjects were unable to compensate this APA shortening by an increase of anticipatory ML centre-of-pressure displacement. Dynamic stability at foot-off was degraded in this population, with a consequent increased risk of ML imbalance and falling. Besides, the effect of temporal pressure on motor synchronization was not affected by ageing. Of particular importance, the synchronization error was greater in elderly than in young subjects, but in the SI condition only. Finally, the third study showed that transitory changes in the mechanical properties of the lower limbs (by ankle loading) affect the order of movement synchronization, but in the RT condition only. With ankle loading, subjects thus switched from a “reactive” to a “predictive” mode of synchronization allowing then to maintain an optimal synchronization. In contrast, ankle loading did not modify the mode of control of the APA. Therefore, it seems that the mode of control of APA and of movement synchronization can be decorrelated according to the biomechanical constraints. These results provide novel insights into the capacity of the CNS to modulate motor synchronization and APA spatio-temporal features to ensure optimal motor coordination and dynamic stability across ages.

An algorithm for generating communicative, human-like motion for social humanoid robots was developed. Anticipation, exaggeration, and secondary motion were demonstrated as examples of communication. Spatiotemporal correspondence was presented as a metric for human-like motion, and the metric was used to both synthesize and evaluate motion. An algorithm for generating an infinite number of variants from a single exemplar was established to avoid repetitive motion. The algorithm was made task-aware by including the functionality of satisfying constraints. User studies were performed with the algorithm using human participants. Results showed that communicative, human-like motion can be harnessed to direct partner attention and communicate state information. Furthermore, communicative, human-like motion for social robots produced by the algorithm allows humans partners to feel more engaged in the interaction, recognize motion earlier, label intent sooner, and remember interaction details more accurately.

This thesis proposes and experimentally demonstrates an approach enabling a humanoid robot to adapt its behaviour to match a human’s behaviour in real-time human-humanoid interaction. The approach uses the information distance synchrony detection method, which is a novel method to measure the behaviour synchrony between two agents, as the core part of the behaviour adaptation mechanism to guide the humanoid robot to change its behaviour in the interaction. The feedback of the participants indicated that the application of this behaviour adaptation mechanism could facilitate human-humanoid interaction. The investigation of motor interference, which may be adopted as a possible metric to quantify the social competence of a robot, is also presented in this thesis. The results from two experiments indicated that both human participants’ beliefs about the engagement of the robot and the usage of rhythmic music might affect the elicitation of the motor interference effects. Based on these findings and recent research supporting the importance of other features in eliciting the interference effects, it can be hypothesized that the overall perception of a humanoid robot as a social entity instead of any individual feature of the robot is critical to elicit motor interference in a human observer’s behaviour. In this thesis, the term ‘overall perception’ refers to the human observer’s overall perception of the robot in terms of appearance, behaviour, the observer’s belief and environmental features that may affect the perception. Moreover, it was found in the motor coordination investigation that humans tended to synchronize themselves with a humanoid robot without being instructed to do so. This finding, together with the behaviour adaptation mechanism, may support the feasibility of bi-directional motor coordination in human-humanoid interaction.

L’objectif de ce travail porte sur l’évaluation des comportements sociaux non-verbauxdans la pathologie schizophrénique. Pour cela, nous avons utilisé la Motor-Affective-Social-Scale (Trémeau et al., 2008) dans le but d’évaluer les gestes co-verbaux qui accompagnent lediscours (sourires et gestes des mains spontanés et expression faciale volontaire), ainsi que leparadigme expérimental des pendules (Schmidt & O’Brien, 1997) permettant d’évaluer lastabilité des coordinations motrices interpersonnelles (CMI). Nos études 1 & 2 démontrentque la schizophrénie induit une réduction significative des gestes co-verbaux, ainsi qu’unediminution de la stabilité des CMI. Nos études 3 & 4 mettent en évidence que la diminutionde la stabilité des CMI dans la schizophrénie est également présente chez les apparentés depremier degré et ce, en dehors de toute influence de l’âge chronologique. Ces résultatssuggèrent que les déficits de CMI pourraient être considérés comme de potentiels phénotypesintermédiaires de la schizophrénie. Enfin, les études 5 & 6 suggèrent qu’il est possible defavoriser la production des comportements sociaux non-verbaux ainsi que de favoriser lastabilité des CMI chez les patients en utilisant une tâche expérimentale d’amorçage socialnon-conscient. Ces travaux ont permis de compléter les connaissances théoriques, de mettreen lumière l’importance des comportements moteurs, de mettre en évidence un nouveaumarqueur phénotypique et d’explorer une nouvelle voie de prise en charge des troubles dufonctionnement social dans la schizophrénie. / The aim of this work was to assess the social motor behaviors in schizophrenia. In ourexperimental situations, we used the Motor-Affective-Social-Scale (Trémeau et al., 2008) toassess the social motor behaviors (spontaneous smiles and hand gestures and voluntary facialexpression) and the hand-held pendulum task (Schmidt & O’Brien, 1997) to assess theinterpersonal social motor coordination. In studies 1 & 2, we showed a social behaviorsreduction and interpersonal social motor coordination impairment in schizophrenia. In studies3 & 4, we showed that first degree-relatives of schizophrenia patients have a similarinterpersonal social motor impairment. These results suggested that interpersonal social motorcoordination could be a potential intermediate phenotype of schizophrenia. Finally, thesestudies 5 & 6 showed that the social motor behaviors, including interpersonal social motorcoordination, could be significantly promoted using pro-social priming effect. In conclusion,this dissertation allowed us to better understand the schizophrenia disorder, to demonstrate thenecessity of taking into account the motor dimensions in mental disorders with socialinteraction deficits, to suggest that intentional interpersonal coordination impairments mightbe a potential motor intermediate phenotype of schizophrenia and to propose a newrehabilitation protocol to improving the social functioning in schizophrenia.

Cette thèse étudie l’effet de quatre facteurs psychosociaux (attractivité physique, émotion, préférence et similitude morphologique) sur la coordination motrice interpersonnelle. A l’aide de la théorie des systèmes dynamiques, nous avons montré que la façon dont nous nous coordonnons avec autrui dépend de ces quatre facteurs. Plus précisément, nous avons étudié la façon dont ces facteurs pouvaient être considérées comme des affordances sociales permettant d’expliquer l’influence des comportements selon les stimuli psychosociaux. D’autre part nous avons également révélé les mécanismes attentionnels et perceptifs (direction du regard) permettant d’expliquer la nature de la relation entre les propriétés psychosociales et les coordinations motrices interpersonnelles. Nos résultats sont en faveur du concept d’embodiment, d'une manière telle que notre comportement exprime nos processus cognitifs internes. Pour conclure, nous pouvons soutenir que la coordination motrice interpersonnelle pourrait être utilisé comme marqueur comportemental pour évaluer les processus psychosociaux au cours d'interactions sociales. / My thesis investigated the effect of four psychosocial factors (physical attractiveness, emotion, likability, and morphological similarity) on interpersonal motor coordination. By adopting the dynamical system approach, we have found that how we behaviorally coordinate with other people was influenced by these four factors. Underlying mechanisms were also explored in the experiments to see whether attention or eye tracking mediated the relation between these psychosocial properties and interpersonal motor coordination. We discussed how these four factors could be viewed as social affordances that afford different coordinated behaviors depending on psychosocial stimuli. Our results are supportive of the embodied concept that cognition is embodied in such a way that our overt behavior manifests inner cognitive processes. In this vein, it is argued that interpersonal motor coordination could be used as behavioral markers to assess psychosocial processes during social interaction.

This study evolved because of the researcher’s need to inquire whether visualmotor integration and fine motor coordination contribute to a child’s readiness to acquire handwriting skills. As school-going age is a controversial topic in the South- African context, the researcher set out to compare the readiness to acquire handwriting skills between two groups of Grade 1 children. This study was developed to determine whether a relationship existed between visual-motor integration and fine motor coordination as part of handwriting readiness, and acquiring handwriting skills in two age groups namely five-year-old children and six-year-old children. Initially the characteristics of the two age groups were determined. This was followed by establishing the level of development for visual-motor integration, fine motor coordination and handwriting skills in both age groups as well as comparing the levels of development. The abovementioned was obtained through the Miller Function and Participation Scales en the Minnesota Handwriting Assessment. Lastly, the scores for visual-motor integration and fine motor integration were correlated to the six categories of the Minnesota Handwriting Assessment. Both age groups presented with overall age appropriate abilities in visual-motor integration and fine motor coordination. The six-year-old group did better on all six of the categories for handwriting in the Minnesota Handwriting Assessment when compared to the five-year-old group. There was a significant difference (p=0.0049) between the visual-motor integration scores between the two age groups. No significant difference between the two age groups was recorded in fine motor coordination. A significant negative correlation was detected between visual-motor integration and the categories of legibility (r=-0.4029), form (r=-0.4300), size (r=-0.4087) and spacing (r=-0.3832) in the five-year-old group. The six-year-old group presented with a strong negative correlation between visual-motor integration and the category of rate (r=-0.3930). When correlating the fine motor coordination score with the categories of the Minnesota Handwriting Assessment, a strong negative correlation was detected with the categories of legibility (r=-0.3850) and spacing (r=-0.4697) in the five-yearold group. The six-year-old group did not present with significant correlations between fine motor coordination and the six categories of the Minnesota Handwriting Assessment. This study confirmed that a relationship exists between visual-motor integration, fine motor integration and handwriting skills. This relationship was not always clear and was influenced by different aspects such as age, maturity as well as the assessment instruments used. This study focused on only one district in Tshwane, which limited the data. The two age groups in this study were not matched for gender, ethnicity and handedness. / Dissertation (MOccTher)--University of Pretoria, 2013. / gm2014 / Occupational Therapy / unrestricted

No description available.

Background: Developmental Coordination Disorder (DCD) describes children with a difficulty to acquire age-specific motor skills. Although there is a significant body of literature addressing developmental and cognitive issues in children with DCD, few studies have actually examined the associations between DCD, physical activity and physical fitness. Therefore, the aim of the present research work was to assess these associations in a series of four successive studies which were set: a) (study 1) to estimate DCD prevalence rates in Greek children and investigate whether these children exhibit different obesity and cardiorespiratory fitness levels than an overseas sample, b) (study 2) to provide evidence on the association between DCD and physical fitness levels, c) (study 3) examine whether a motor skills and exercise training intervention programme affects motor proficiency in a cohort of elementary school children with and without DCD, and d) (study 4) to test the hypothesis that DCD is associated with CVD risk, identify modes of physical activity that mediate such an association and to evaluate the CSAPPA scale as a potential tool for identifying Greek children for DCD. Methods: The total of 574 Greek (Age: 11.46 ± 1.54 years; BMI: 19.96 ± 3.53) children were assessed for anthropometry, physical fitness (flexibility, hand strength, leg explosive power, speed and cardiorespiratory fitness), motor competence (i.e., short form of the Bruininks-Oseretsky Test of Motor Profiency- BOTMP-sf) and subjected to two self assessments for: i) perception of adequacy for physical activity (CSAPPA scale), and ii) children’s participation in physical activity (Participation Questionnaire - PQ). Results: Study 1: Greek children demonstrated significantly higher DCD prevalence rates (p<0.05), higher body fat (p<0.05) and were inferior in both cardiorespiratory fitness (p<0.05) and motor competence (p<0.05) compared to an overseas sample. Study 2: Greek children with DCD demonstrated significantly higher BMI values (p<0.01) and lower leg explosive power (p<0.01), speed (p<0.01) and hand strength (p<0.01) than those without DCD. Study 3: Results showed a significant main effect of time [F(14, 115) = 3.79, p< 0.001; η2 = 0.32] for motor competence (p<0.001) between children with and without DCD. Significant main effects of group (i.e intervention and control groups) [F(42, 351) = 4.01, p< 0.001; η2 = 0.33] were observed for BMI (p<0.01), motor competence (p<0.01), cardiorespiratory fitness (p<0.01), hand strength (p<0.05), leg explosive power (p<0.05), speed (p<0.01), and free time play activities (p<0.05). Study 4: Chi-square comparisons and ANOVA, revealed significantly increased body mass (p<0.05), BMI (p<0.05) and inactivity (p<0.05), as well as significantly decreased cardiorespiratory fitness (p<0.05), motor competence (p<0.05), CSAPPA indices, and participation in free play (p<0.05) in children with DCD. Furthermore, BMI and cardiorespiratory fitness were significantly associated with motor competence (p<0.05) with inactivity as the mediating factor (p<0.05). ROC curve analyses for CSAPPA indicated an optimal cut-off at 62 points. Conclusions: 1) the relatively high DCD and obesity prevalence rates together with the low cardiorespiratory fitness suggest greater health risk for Greek children with the studied condition, 2) children with DCD tend to perform worse in selected physical fitness parameters compared to their normal peers, 3) motor skills and exercise training interventions for children with DCD may improve health and skills related fitness, and 4) inactivity mediates the relationship between DCD and CVD risk in children with DCD. Finally, the CSAPPA scale may serve as a practical and a cost-effective proxy assessment for identifying Greek children with DCD, however as this is not a standardised test for use with children, its use should be treated with caution until further validation work.

A moxidectina é uma droga antiparasitária, do grupo das milbemicinas, utilizada em animais domésticos. Em mamíferos seu mecanismo de ação envolve o GABA, neurotansmissor que tem um papel relevante na regulação do comportamento sexual. Assim, o presente trabalho estudou os efeitos da moxidectina no comportamento sexual de ratos machos. Uma vez que alterações na função motora podem interferir na manifestação deste comportamento, avaliou-se, inicialmente, a atividade geral no campo aberto e a coordenação motora na trave elevada, e posteriormente, o comportamento sexual de ratos inexperientes e experientes. A avaliação da atividade geral dos ratos observados no campo aberto mostrou que, mesmo em altas doses (2,0 e 20,0mg/kg), a moxidectina não altera o comportamento de ratos no campo aberto. Esta droga, porém, prejudicou a coordenação motora dos animais avaliados na trave elevada, sendo este efeito atribuído, ao menos em parte, à ação da moxidectina em receptores GABAérgicos. Os resultados obtidos na avaliação do comportamento sexual de ratos inexperientes mostraram redução da motivação sexual dos animais que receberam 0,2mg/kg de moxidectina e foram observados 24 ou 72horas depois. Nenhuma alteração significante foi observada nos diferentes parâmetros do comportamento sexual dos ratos experientes, indicando que a experiência sexual pode reverter os efeitos desta droga. Estes resultados mostraram que a moxidectina prejudicou o comportamento sexual de ratos machos inexperientes e a coordenação motora, efeitos estes atribuídos a uma ação central desta droga em receptores GABAA. / The moxidectin is an antiparasitic drug that is used in domestic animals. It is a semi-synthetic milbemycin. Its mechanism of action, in mammals, involves GABA, neurotransmiter that has an important role in the regulation of the sexual behavior. Thus, the present work studied the effects of the moxidectin in male rats sexual behavior. Due to the fact that alterations in the motor function can interfere in the expression of this behavior, it was evaluated, initially, the general activity in the open field and the motor coordination at wooden dowel, and later, the sexual behavior of naïve and experienced rats. The evaluation of the general activity of the rat observed in the open field showed that, even in high doses (2.0 and 20.0 mg/kg), the moxidectin do not alter the behavior of the rats in open field. However, this drug was able to impair the motor coordination of the animals at the wooden dowel. As a matter of fact, this effect is due, at least part of it, to the action of the moxidectin in GABAergics receptors. The results achieved in the evaluation of naïve male rats’ sexual behavior showed reduction of the sexual motivation of the animals that received 0.2 mg/kg of moxidectin and were observed after 24 or 72 hours later. No significant alteration was detected in the various parameters of the experienced rats’ sexual behavior, indicating that the sexual experience could revert the effects of this drug. The moxidectin impair the sexual behavior of naive male rats and the motor coordination, and the reasons that caused these effects were attributed to a central action of the moxidectin at GABAA receptors.

Parce que l’homme évolue dans un système en mouvement permanent, il a l’obligation de s’y adapter au mieux. Pour cela il dispose d’un ensemble de récepteurs lui permettant de s’adapter, de suivre et de prendre en compte l’évolution et la variation des différents éléments composant son environnement. La perception du monde traduit ainsi la capacité de l’individu à prendre conscience de la présence d’un évènement particulier à un moment donné. C’est dans ce contexte que se situe cette étude. En station droite érigée, l’ajout d’une modalité haptique permet-elle au sujet d’améliorer ses comportements posturaux ? Selon Matthews et Miles (1988) le sens haptique correspond au sens de la perception combinant les informations dynamiques issues à la fois des récepteurs cutanés, musculaires, articulaires et tendineux. De nombreux auteurs (Jeka et Lackner 1994, 1995 ; Jeka et coll., 1997, 1998 ; Lackner et coll., 1999 ; Rabin et coll., 1999, 2008) ont montré que les informations haptiques obtenues par un contact du bout du doigt avec une surface rigide inférieur à 1Newton, contact qui mécaniquement ne permet pas une augmentation de la base de sustentation, fournissent des informations essentielles au système nerveux central (SNC) lui permettant une diminution des oscillations posturales. Le but de ce travail est de comprendre et d’interpréter les effets d’un toucher léger du bout d’un doigt avec une surface rigide dans le maintien et le contrôle de la stabilité posturale d’un sujet en position droite érigée, au moyen d’outils stabilométriques classiques tels que l’amplitude, la surface, etc. Ainsi que les coordinations posturales mises en place au travers de l’analyse en composantes principales et des intercorrélations pour étudier les coordinations articulaires et l’analyse de la diffusion et de la récurrence du stabilogramme pour analyser le résultat net de ces coordinations (qualitatif et quantitatif). / Because human evolves in a system in permanent movement, he has the obligation to adapt itself to it at best. So, he has of a set of receptor allowing him to adapt itself, to follow and to take into account the evolution and the variation of the various elements composing his environment. The perception of the environment translates the capacity of the subject to become aware of the presence of a particular event at a given moment. It is in this context that is situated this study. According to Matthews and Miles (1988) the haptique sense corresponds to the perceptual sense combining the stemming dynamic information at the same time cutaneous, muscular, articular and tendinous receptors. Authors showed (Jeka et Lackner 1994, 1995 ; Jeka et coll., 1997, 1998 ; Lackner et coll., 1999 ; Rabin et coll., 1999, 2008) that the haptic information obtained by a fingertip contact with a rigid pad lower 1 Newton, a contact which mechanically does not allow an increase of the support base, provide essential information to the central nervous system (SNC) allowing him a decrease of the postural oscillations. The aim of this work is to understand and to interpret the effects of a light touch of the fingertip with a rigid pad in the preservation and the control of postural stability of a subject in upright posture, by means of stabilometrics classical tools such as the amplitude, the surface, etc. As well as the set up motor coordination through the analysis in main components and intercorrelations to study the articular coordination and the analysis of the diffusion and the recurrence of the stabilogramme to analyze the result of these coordinations (qualitative and quantitative).