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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Descending neural drives to ankle muscles during gait and their relationships with clinical functions in patients after stroke / 脳卒中後片麻痺患者における歩行時の足関節周囲筋に対する下行性入力と臨床的機能指標との関連

Kitatani, Ryosuke 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(人間健康科学) / 甲第19640号 / 人健博第32号 / 新制||人健||3(附属図書館) / 32676 / 京都大学大学院医学研究科人間健康科学系専攻 / (主査)教授 黒木 裕士, 教授 坪山 直生, 教授 黒田 知宏 / 学位規則第4条第1項該当 / Doctor of Human Health Sciences / Kyoto University / DFAM
2

Measuring the Relationship Between Reflexive and Intentional ANS Response

Pardikes, Thomas James 30 June 2008 (has links)
The dynamic behaviors of a complex organism are explained via voluntary and involuntary action. One underpinning of this system is organized and facilitated by the autonomic nervous system, integrating information from conscious and non-conscious centers in a seemingly hierarchical fashion. As a result, voluntary actions have the ability to inhibit reflexive actions via an inhibitory circuit. 111 subjects performed four diverse autonomic tasks consisting of voluntary and involuntary combinations. Analysis supports the proposed hierarchical model. Each task evoked specific autonomic states. Voluntary tasks influenced autonomic actions more than involuntary tasks. And working memory capacity mediated voluntary control. / Master of Science
3

Vliv klenby a nastavení akra horní končetiny v opoře na koaktivaci svalových řetězců - pilotní studie / Impact of Arches and Acral Parts of Upper Limbs in Prop up Position on Coactivation of Muscle Chains - Pilot Study

Ballýová, Monika January 2016 (has links)
Bibliografický záznam BALLÝOVÁ, Monika. Impact of Arches and Acral Parts of Upper Limbs in Prop up Position on Coactivation of Muscle Chains - Pilot Study. Prague: Charles University, 2nd Faculty of Medicine, Department of Rehabilitation and Sports, 2016, 70 p., Supervisor: PhDr. Ingrid Palaščáková Špringrová, Ph.D. Abstract The Acral Coactivation Therapy, based on neurophysiology, is a method the principle of which consists in propping up on acral parts of the limbs with the aim to coactivate ventral and dorsal muscle chains in order to center the root joints and to straighten the axial skeleton subsequently. The practical part of the thesis is aimed at verification of the Acral Coactivation Therapy principles. Two groups of individuals were objects of the research: mountaineers and general population. Normal arches of upper limbs statistically prevailed in the group of the mountaineers, which proves the impact of regular physical activity on musculoskeletal system and its function. Surface electromyography recorded the impact of correction of the acral part on change in muscular activity. The results of the electromyographic measurement showed the same trends in muscular activity changes as the outcomes resulting from the Acral Coactivation Therapy. Statistically, the most substantial changes were...
4

Modulation de l'activité musculaire pendant la marche de l'enfant : vers une modélisation de l'EMG dynamique / Modulation of muscle activity in children’s gait : towards a modelling of dynamic electromyography

Gross, Raphaël 12 September 2017 (has links)
La marche des enfants atteints de paralysie cérébrale est explorée dans des structures appelées laboratoires d’analyse quantifiée du mouvement depuis environ 30 ans. L’interprétation des données acquises dans ces laboratoires est difficile en raison d’obstacles méthodologiques, statistiques, et parce que la physiologie motrice n’est pas totalement connue. L’étude des signaux électromyographiques, indicateurs des activations musculaires dynamiques, fait l’objet de cette thèse. Nous avons effectué deux séries d’expérimentations aboutissant à quatre études de recherche sur la marche des enfants à développement typique et des enfants atteints de paralysie cérébrale unilatérale. L’effet de la vitesse de marche sur la coactivation musculaire, le lien entre cette coactivation et l’amplitude des mouvements du membre inférieur pendant la marche, les adaptations musculaires lors de la marche en virage, et les spécificités de ces adaptations chez les enfants paralysés cérébraux, ont été successivement étudiées. Ces résultats nous ont permis de préciser le rôle de facteurs physiologiques liés à la commande motrice, tels que la vitesse ou le changement de direction, mais également l’effet de la pathologie sur les activations musculaires observées. Les difficultés métrologiques et statistiques liées aux signaux étudiés ont cependant constitué des obstacles importants à l’interprétation de ces données en termes de contrôle moteur. La réflexion progressive sur ces problèmes méthodologiques a permis le développement par étapes de traitements statistiques spécifiques, parfois innovants, et l’émergence de propositions concernant la métrologie de l’électromyographie dynamique. / Children with cerebral palsy benefit from gait analyses in motion labs for approximately thirty years. The interpretation of the numerous data that can be obtained during such evaluations still remains cautious, because of methodological and statistical reasons, and because of the lack of an exhaustive knowledge regarding the motor control of gait. This Ph D thesis focused on the study of electromyographic signals, which are representative of the dynamic muscle activations during gait. We designed two series of experiments, leading to four studies into the dynamic electromyography during gait in children with unilateral cerebral palsy and their typically developing peers. The effect of gait speed on muscle coactivation, the impact of this coactivation on the range of motion during gait, the muscle adaptations to turning gait, and finally the specificities of these adaptations in children with cerebral palsy were investigated successively. The results of the studies give insight into the role of physiological factors linked to the motor control of gait, such as speed or change of direction, but also into the impact of pathology on the muscle activations, which are the parameters of interest. Some methodological and statistical difficulties, linked to the nature of the signals that are studied, compromise the possibility to interpret the data with respect to motor control. The continuous reflection on these methodological limitations allows the development of specific, appropriate statistical analyses, and the emergence of propositions regarding the metrology of dynamic electromyography.
5

Redundancy gain : manifestations, causes and predictions

Engmann, Sonja 04 1900 (has links)
Les temps de réponse dans une tache de reconnaissance d’objets visuels diminuent de façon significative lorsque les cibles peuvent être distinguées à partir de deux attributs redondants. Le gain de redondance pour deux attributs est un résultat commun dans la littérature, mais un gain causé par trois attributs redondants n’a été observé que lorsque ces trois attributs venaient de trois modalités différentes (tactile, auditive et visuelle). La présente étude démontre que le gain de redondance pour trois attributs de la même modalité est effectivement possible. Elle inclut aussi une investigation plus détaillée des caractéristiques du gain de redondance. Celles-ci incluent, outre la diminution des temps de réponse, une diminution des temps de réponses minimaux particulièrement et une augmentation de la symétrie de la distribution des temps de réponse. Cette étude présente des indices que ni les modèles de course, ni les modèles de coactivation ne sont en mesure d’expliquer l’ensemble des caractéristiques du gain de redondance. Dans ce contexte, nous introduisons une nouvelle méthode pour évaluer le triple gain de redondance basée sur la performance des cibles doublement redondantes. Le modèle de cascade est présenté afin d’expliquer les résultats de cette étude. Ce modèle comporte plusieurs voies de traitement qui sont déclenchées par une cascade d’activations avant de satisfaire un seul critère de décision. Il offre une approche homogène aux recherches antérieures sur le gain de redondance. L’analyse des caractéristiques des distributions de temps de réponse, soit leur moyenne, leur symétrie, leur décalage ou leur étendue, est un outil essentiel pour cette étude. Il était important de trouver un test statistique capable de refléter les différences au niveau de toutes ces caractéristiques. Nous abordons la problématique d’analyser les temps de réponse sans perte d’information, ainsi que l’insuffisance des méthodes d’analyse communes dans ce contexte, comme grouper les temps de réponses de plusieurs participants (e. g. Vincentizing). Les tests de distributions, le plus connu étant le test de Kolmogorov- Smirnoff, constituent une meilleure alternative pour comparer des distributions, celles des temps de réponse en particulier. Un test encore inconnu en psychologie est introduit : le test d’Anderson-Darling à deux échantillons. Les deux tests sont comparés, et puis nous présentons des indices concluants démontrant la puissance du test d’Anderson-Darling : en comparant des distributions qui varient seulement au niveau de (1) leur décalage, (2) leur étendue, (3) leur symétrie, ou (4) leurs extrémités, nous pouvons affirmer que le test d’Anderson-Darling reconnait mieux les différences. De plus, le test d’Anderson-Darling a un taux d’erreur de type I qui correspond exactement à l’alpha tandis que le test de Kolmogorov-Smirnoff est trop conservateur. En conséquence, le test d’Anderson-Darling nécessite moins de données pour atteindre une puissance statistique suffisante. / Response times in a visual object recognition task decrease significantly if targets can be distinguished by two redundant attributes. Redundancy gain for two attributes is a common finding, but redundancy gain from three attributes has been found only for stimuli from three different modalities (tactile, auditory, and visual). This study extends those results by showing that redundancy gain from three attributes within the visual modality is possible. It also provides a more detailed investigation of the characteristics of redundancy gain. Apart from a decrease in response times for redundant targets, these include a decrease in minimal response times and an increase in symmetry of the response time distribution. This study further presents evidence that neither race models nor coactivation models can account for all characteristics of redundancy gain. In this context, we discuss the problem of calculating an upper limit for the performance of race models for triple redundant targets, and introduce a new method of evaluating triple redundancy gain based on performance for double redundant targets. In order to explain the results from this study, the cascade race model is introduced. The cascade race model consists of several input channels, which are triggered by a cascade of activations before satisfying a single decision criterion, and is able to provide a unifying approach to previous research on the causes of redundancy gain. The analysis of the characteristics of response time distributions, including their mean, symmetry, onset, and scale, is an essential tool in this study. It was therefore important to find an adequate statistical test capable of reflecting differences in all these characteristics. We discuss the problem and importance of analysing response times without data loss, as well as the inadequacy of common methods of analysis such as the pooling of response times across participants (e.g. Vincentizing) in the present context. We present tests of distributions as an alternative method for comparing distributions, response time distributions in particular, the most common of these being the Kolmogorov-Smirnoff test. We also introduce a test yet unknown in psychology: the two-sample Anderson-Darling test of goodness of fit. We compare both tests, presenting conclusive evidence that the Anderson-Darling test is more accurate and powerful: when comparing two distributions that vary (1) in onset only, (2) in scale only, (3) in symmetry only, or (4) that have the same mean and standard deviation but differ on the tail ends only, the Anderson-Darling test proves to detect differences better than the Kolmogorov-Smirnoff test. Finally, the Anderson-Darling test has a type I error rate corresponding to alpha whereas the Kolmogorov-Smirnoff test is overly conservative. Consequently, the Anderson- Darling test requires less data than the Kolmogorov-Smirnoff test to reach sufficient statistical power.
6

Redundancy gain : manifestations, causes and predictions

Engmann, Sonja 04 1900 (has links)
Les temps de réponse dans une tache de reconnaissance d’objets visuels diminuent de façon significative lorsque les cibles peuvent être distinguées à partir de deux attributs redondants. Le gain de redondance pour deux attributs est un résultat commun dans la littérature, mais un gain causé par trois attributs redondants n’a été observé que lorsque ces trois attributs venaient de trois modalités différentes (tactile, auditive et visuelle). La présente étude démontre que le gain de redondance pour trois attributs de la même modalité est effectivement possible. Elle inclut aussi une investigation plus détaillée des caractéristiques du gain de redondance. Celles-ci incluent, outre la diminution des temps de réponse, une diminution des temps de réponses minimaux particulièrement et une augmentation de la symétrie de la distribution des temps de réponse. Cette étude présente des indices que ni les modèles de course, ni les modèles de coactivation ne sont en mesure d’expliquer l’ensemble des caractéristiques du gain de redondance. Dans ce contexte, nous introduisons une nouvelle méthode pour évaluer le triple gain de redondance basée sur la performance des cibles doublement redondantes. Le modèle de cascade est présenté afin d’expliquer les résultats de cette étude. Ce modèle comporte plusieurs voies de traitement qui sont déclenchées par une cascade d’activations avant de satisfaire un seul critère de décision. Il offre une approche homogène aux recherches antérieures sur le gain de redondance. L’analyse des caractéristiques des distributions de temps de réponse, soit leur moyenne, leur symétrie, leur décalage ou leur étendue, est un outil essentiel pour cette étude. Il était important de trouver un test statistique capable de refléter les différences au niveau de toutes ces caractéristiques. Nous abordons la problématique d’analyser les temps de réponse sans perte d’information, ainsi que l’insuffisance des méthodes d’analyse communes dans ce contexte, comme grouper les temps de réponses de plusieurs participants (e. g. Vincentizing). Les tests de distributions, le plus connu étant le test de Kolmogorov- Smirnoff, constituent une meilleure alternative pour comparer des distributions, celles des temps de réponse en particulier. Un test encore inconnu en psychologie est introduit : le test d’Anderson-Darling à deux échantillons. Les deux tests sont comparés, et puis nous présentons des indices concluants démontrant la puissance du test d’Anderson-Darling : en comparant des distributions qui varient seulement au niveau de (1) leur décalage, (2) leur étendue, (3) leur symétrie, ou (4) leurs extrémités, nous pouvons affirmer que le test d’Anderson-Darling reconnait mieux les différences. De plus, le test d’Anderson-Darling a un taux d’erreur de type I qui correspond exactement à l’alpha tandis que le test de Kolmogorov-Smirnoff est trop conservateur. En conséquence, le test d’Anderson-Darling nécessite moins de données pour atteindre une puissance statistique suffisante. / Response times in a visual object recognition task decrease significantly if targets can be distinguished by two redundant attributes. Redundancy gain for two attributes is a common finding, but redundancy gain from three attributes has been found only for stimuli from three different modalities (tactile, auditory, and visual). This study extends those results by showing that redundancy gain from three attributes within the visual modality is possible. It also provides a more detailed investigation of the characteristics of redundancy gain. Apart from a decrease in response times for redundant targets, these include a decrease in minimal response times and an increase in symmetry of the response time distribution. This study further presents evidence that neither race models nor coactivation models can account for all characteristics of redundancy gain. In this context, we discuss the problem of calculating an upper limit for the performance of race models for triple redundant targets, and introduce a new method of evaluating triple redundancy gain based on performance for double redundant targets. In order to explain the results from this study, the cascade race model is introduced. The cascade race model consists of several input channels, which are triggered by a cascade of activations before satisfying a single decision criterion, and is able to provide a unifying approach to previous research on the causes of redundancy gain. The analysis of the characteristics of response time distributions, including their mean, symmetry, onset, and scale, is an essential tool in this study. It was therefore important to find an adequate statistical test capable of reflecting differences in all these characteristics. We discuss the problem and importance of analysing response times without data loss, as well as the inadequacy of common methods of analysis such as the pooling of response times across participants (e.g. Vincentizing) in the present context. We present tests of distributions as an alternative method for comparing distributions, response time distributions in particular, the most common of these being the Kolmogorov-Smirnoff test. We also introduce a test yet unknown in psychology: the two-sample Anderson-Darling test of goodness of fit. We compare both tests, presenting conclusive evidence that the Anderson-Darling test is more accurate and powerful: when comparing two distributions that vary (1) in onset only, (2) in scale only, (3) in symmetry only, or (4) that have the same mean and standard deviation but differ on the tail ends only, the Anderson-Darling test proves to detect differences better than the Kolmogorov-Smirnoff test. Finally, the Anderson-Darling test has a type I error rate corresponding to alpha whereas the Kolmogorov-Smirnoff test is overly conservative. Consequently, the Anderson- Darling test requires less data than the Kolmogorov-Smirnoff test to reach sufficient statistical power.
7

Coactivation in sedentary and active older adults during maximal power and submaximal power tasks : activity-related differences

Newstead, Ann Hamilton 20 October 2010 (has links)
As adults age, they lose the ability to produce maximal power and speed of movement. Success in daily living is often dependent upon power and speed. Thus these age-related decrements in performance can reduce physical independence and quality of life. An active lifestyle in older adulthood is associated with more successful aging. The purpose of this research program was to define the link between habitual activity and performance, specifically in regard to activities requiring power and speed. The hypothesis was that active older adults, compared to sedentary older adults, would be characterized by greater power production in maximal- and submaximal-effort tasks. Grouping older adults by activity level, coactivation was associated with activity level. Functional tasks are performed with a range of power requirements. Coactivation was used to distinguish groups in a maximal power task (Study 1) and submaximal power tasks (Study 2). In Study 1, the young adults demonstrated a greater maximal power than the older adults. While maximal power was not different between the older active and sedentary groups, the groups did differ on how they created maximal power. The active older adults produced a greater coactivation in the lower leg muscles compared to the older sedentary adults. In Study 2, the active older adults responded to different speeds during a submaximal power task with greater coactivation in the muscles of the lower leg at slow speeds compared with the sedentary older adults. Both older adults groups increased coactivation in the thigh muscles at high speeds. The sedentary older adults responded to speed with increased coactivation in the lower leg at fast speeds. The active older adults increased proximal thigh coactivation, EMG index, at the fastest speed compared with the sedentary older adults. Both older adult groups showed muscle activation adaptation to the change in task demands. The results of this dissertation increase our understanding about the link between physical activity and performance. Age-related differences in coactivation were observed during both maximal and submaximal tasks. Activity-related differences were observed suggesting the active older adults have a greater capability to adjust muscle activity to meet the challenges of community living. / text
8

Redundancy gain: correlations across s sensory modalities from a neurologically normal population

Keifer, Orion Paul, Jr. 06 August 2009 (has links)
One of the most basic reaction time experiments employed by psychologists is the comparison of latencies to responses for single and redundant targets. The general effect is that participants are capable of responding faster, that is having shorter response latencies when redundant stimuli, as opposed to an individual stimulus, are presented. Interestingly, several models attempting to predict this effect, including the well known race model, have not been entirely successful. The following study evaluated redundancy gain and violations of the race model, in three experimental models: visual only, auditory only, and a visual-auditory bimodal paradigm. The results showed redundancy gain in all three paradigms, but they were only significant violations of the race model for the visual-auditory condition. Additionally, correlations between the different paradigms were explored with respect to redundancy gain and violations of the race model on an individual participant basis.
9

Efeito de um treinamento de FNP sobre variáveis biomecânicas em idosos caidores

Pereira, Marcelo Pinto [UNESP] 18 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-18Bitstream added on 2014-06-13T18:49:48Z : No. of bitstreams: 1 pereira_mp_me_rcla.pdf: 922464 bytes, checksum: 88c79b720bc8fbb69fd20e9cb7485e7d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O principal objetivo dessa Dissertação foi avaliar o desempenho em contrações isométricas de flexo-extensão do joelho e o padrão da marcha em indivíduos idosos com potencial para sofrerem quedas e avaliar o efeito de um treinamento sobre essas variaveis. Quinze mulheres (71,67+6,60 anos), caidoras, as quais foram divididas aleatoriamente em dois grupos (Grupo Treino – GT; e Grupo Controle – GC) realizaram testes antes e após um período de treinamento de 10 semanas de Facilitação Neuromuscular Proprioceptiva (FNP): i) Aplicação da Escala de Equilíbrio de Berg (EEB), contrações isométricas voluntárias máximas de flexão e extensão do joelho; ii) marcha por vinte minutos na velocidade de preferência; iii) analise da marcha a 2km/h, 3km/h, 4km/h e na velocidade de preferência. Nos testes de contração máxima a Taxa de Desenvolvimento de Força (TDF) e força máxima foram obtidas. O registro eletromiografico (EMG) de Root Mean Square (RMS), freqüência mediana (FM) e Indice de Co-ativação (IC) entre músculos vasto-lateral (VL), vasto-medial (VM), reto-femoral e bíceps femoral (BF) foram determinados. Durante o teste de marcha por 20 minutos foram adquiridos os registros EMG dos VL, RF, VM, BF, tibial anterior (TA), fibular longo (FB), gastrocnêmio medial (GM) e gastrocnêmio lateral (GL) em três diferentes períodos do protocolo (no inicio, no meio e no final do protocolo). Ainda, esses registros foram obtidos em quatro diferentes fases da marcha: pré-contato do calcâneo no solo (Pré), durante o toque do mesmo (Toque), durante a retirada dos dedos (Retirada) e durante todo o ciclo da marcha (Ciclo). Também foram determinadas as seguintes variáveis cinemáticas: freqüência e comprimento de passada, velocidade do calcâneo no momento do seu toque no solo (VEL), sua aceleração mínima prévia ao toque e tempo de apoio. Por fim, no protocolo com quatro... / The main objective of this Dissertation was to evaluate the knee flexion-extension isometric performance and gait pattern in elderly fallers and to evaluate a training course effect on these variables. Fifteen elderly female fallers (71.67+6.60 years), randomly divided into two groups (Training Group - TG, and Control Group - GC), performed a tests battery before and after 10 weeks of Proprioceptive Neuromuscular Facilitation training period, consisting of: i) The Berg Balance Scale (BBS) application, knee extension and flexion isometric contractions, ii) twenty minutes gait at their preferred walking speed, iii) gait analysis at 2km/h, 3 km/h; 4km/h and in their preferred walking speed. In maximum knee flexion and extension contractions the Rate of Development Force (TDF) was achieved in as the maximal force, the electromyography (EMG) Root Mean Square (RMS), median frequency (MF) and Coactivation Index (IC) from vastus-lateralis (VL), vastus-medialis (VM), rectusfemoris (RF) and biceps femoris (BF) muscles. During the 20 minutes walking test the EMG signal from VL, RF, VM, BF, tibialis anterior (TA), fibularis longus (FB), medial gastrocnemius (GM) and lateral gastrocnemius (GL) in three different Protocol periods (at the beginning, medial and at the end). These records were obtained in four different gait phases: Pre-contact (Pre), during the the heel contact (Contact), at the toe-off and throughout the entire gait cycle. The EMG data were also used to determine CI during gait. Also the following kinemetry variables were measured: step length and frequency, heel velocity during its strike on the ground (VEL) and its minimal acceleration previous the heel strike. Finally, during the four speed protocol the VEL, CI around knee and ankle and the RMS and MF were determined at Pre, Contact and Cycle. The results show that during isometric contractions the CI is related significantly with... (Complete abstract click electronic access below)
10

Mechanisms of Slowed Foot Tap Speed in Older Adults

Hartman, Erica L 13 July 2016 (has links)
Rapid repetitive tapping, like the Foot Tap Test (FTT), slows with age, but the underlying mechanisms are unknown. Purpose: 1. Test the hypotheses that greater performance variability, increased muscle coactivation, and slowed muscle contractile speeds are related to lower foot tap count (FTC) in older adults; 2. Examine the relationship between FTC and physical function in older adults, using the advanced SPPB-A. Methods: 18 (25.0±3.1years, 9F, mean±SD), and 28 (73.4±4.9, 14F) adults were recruited; the later were divided into Higher (HFO) and Lower (LFO) Functioning based on SPPB-A score. Participants performed 10s of rapid tapping (FTT) while seated. A MATLAB program was used to calculate FTC and variability of the intertap-interval (COV-ITI). Contractile speed (rates of force development and relaxation, RFD and RFR) of the dorsiflexor muscles were determined using ballistic contractions. Electromyography was recorded on the tibialis anterior, soleus, and coactivation was calculated based on their agreement. Results: LFO had a lower FTC than Young and HFO (45.9±7.0taps, 54.4±7.5, 53.1±5.7, respectively; p=0.003), and lower COV-ITI than Young (12.3±5.9%, 20.5±8.1, respectively, p=0.009). No associations were found between COV-ITI and FTC. Coactivation was higher in Young than HFO (0.568±0.209, 0.321±0.129) and was negatively related to FTC in older (r2=0.274, p=0.005). The LFO had a slower RFD than Young and FTC was positively related to maximal RFD (r2=0.345, p=0.001) and RFR (r2=0.162, p=0.038) in older adults. In older, FTC was related to SPPB-A (r2=0.329, p=0.001). Conclusions: Greater coactivation during the FTT and slower force development may negatively affect FTC in older adults.

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