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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.
41

Využití virtuální reality ke zhodnocení dynamické posturální stability u hráčů beachvolejbalu / Use of virtual reality to evaluate dynamic postural stability in beachvoleyball players

Hlaváčková, Anna January 2017 (has links)
Title: Use of virtual reality to evaluate the dynamic postural stability in beachvoleyball players Objectives: The aim of the study was to evaluate if the dynamic postural stability of trained beachvoleyball players is affected by training. Also I tried to evaluate, if the final score of equilibrium will be higher, than in regular population. For testing was also used virtual reality to stimulate vestibular apparatus. Virtual reality was used as a disturbing element. NeuroCom Smart Equi Test was used as an evaluation factor of dynamic postural stbility. Methods: The research involved a total of 20 females - 10 beachvoleyball players and 10 healthy persons performing activities of daily living. We investigated dynamic postural stability on device called NeuroCom Smart Equi Test. For evaluation of dynamic postural stability was used Head Shake Test - Sensory Organisation Test. This test was taken twice, second time after intervetion by virtual reality. Data were analyzed by statistical t-test method. Result: Statisticly significant result was found only in the case of a Sensory Organisation Test condiition 5 and 6 in comparison between both groups and Head Shake test-SOT2 in latero- lateral movement of the head at the controle group. The results confirmed the effect of playing beachvoleyball on...
42

Interação entre as áreas funcionais do sistema visual e do sistema vestibular: estudo com RMF e EGV

Justina, Hellen Mathei Della 21 February 2014 (has links)
CAPES, CNPq / O equilíbrio estático corporal é comandado por três sistemas sensoriais: o sistema vestibular, responsável pelas informações sobre a posição e os movimentos da cabeça; o sistema visual, que informa a posição espacial dos objetos em relação ao nosso corpo; e o sistema proprioceptivo, que controla a postura e a movimentação corporal. Estes três sistemas devem funcionar sempre em sintonia, caso contrário, o indivíduo apresentará problemas de equilíbrio. Dessa forma, é importante caracterizar as regiões corticais, bem como suas interações, envolvidas neste processo. Para isto, é necessário a utilização de técnicas de neuroimagem funcional, sendo a ressonância magnética funcional (RMf) uma das técnicas mais utilizadas neste campo nos dias de hoje. Entretanto, uma grande parte dos experimentos de RMf requer o uso de aparelhos eletrônicos para produzir estimulações somatosensoriais no corpo humano, onde a principal dificuldade é o seu ambiente hostil aos circuitos eletrônicos. A estimulação galvânica vestibular é um dos métodos mais utilizados para estimular o sistema vestibular. Esta consiste em fornecer uma corrente de baixa amplitude diretamente nas aferências vestibulares, a qual atua no disparo dos neurônios vestibulares primários atingindo principalmente as aferências otolíticas e as fibras dos canais semicirculares. O objetivo deste trabalho é analisar e avaliar as áreas cerebrais envolvidas com as estimulações visual e galvânica vestibular e suas interações, utilizando a técnica de RMf e um estimulador galvânico vestibular. Para tanto, como primeira etapa desta pesquisa, validou-se in vivo um estimulador galvânico vestibular. O estimulador elétrico não interferiu de forma significativa na qualidade das imagens de ressonância magnética e pode ser utilizado com segurança nos experimentos de RMf. Testes foram realizados para determinar um eletrodo suficientemente confortável para o voluntário durante a estimulação galvânica vestibular e que não causasse artefato nas imagens. Após estas etapas concluídas, 24 voluntários foram selecionados para realizarem três tarefas: uma puramente visual (um tabuleiro de xadrez piscante no centro da tela), uma puramente vestibular (pela aplicação da estimulação galvânica vestibular) e uma simultânea, com a apresentação em conjunto dos estímulos visual e vestibular. A estimulação puramente visual mostrou ativação dos córtices visual primário e associativo, enquanto que a estimulação puramente vestibular levou a ativação das principais áreas envolvidas com a função multimodal do sistema vestibular, como o córtex parietoinsular vestibular, o lóbulo parietal inferior, o giro temporal superior, o giro pré-central e o cerebelo. A estimulação simultânea dos sistemas visual e vestibular resultou na ativação dos giros frontal médio e inferior. Além do padrão de interação visual-vestibular inibitório recíproco ter sido mais evidente durante a condição simultânea, observou-se que as regiões frontais (córtex dorsomedial pré-frontal e giro frontal superior) estão envolvidas com o processamento da função executiva quando existem informações conflitantes dos sistemas visual e vestibular. / The static body equilibrium is controlled by three sensory systems: the vestibular system, responsible for informing the position and the movements of the head; the visual system, which informs the spatial objects position relative to the body; and the proprioceptive system, which controls posture and body movements. These three systems must always work in harmony, otherwise the individual will present balance problems. Thus, it is important to characterize the cortical regions, as well as their interactions, involved in this process. For this it is necessary to use functional neuroimaging techniques, the functional magnetic resonance imaging (fMRI) is one of the most used techniques in this field nowadays. However, a large fMRI experiments require the use of electronic devices for producing somatosensory stimulation in the human body, where the main difficulty is its hostile environment for electronic circuits. The galvanic vestibular stimulation is one of the most used methods to stimulate the vestibular system. This stimulation consist of applying a low current amplitude directly on vestibular afferents, which acts firing the primary vestibular neurons, affecting the otolithic afferents and the semicircular canals fibers. The objective of this work is to evaluate and analyze the brain areas involved with visual and galvanic vestibular stimulations and their interactions using fMRI. Therefore, as a first step of this research, a galvanic vestibular stimulator was validated in vivo. The electrical stimulator did not interfere in a significance way on magnetic resonance images quality and could be safely used in fMRI experiments. Tests were performed to select an electrode sufficiently comfortable for the volunteer during the galvanic vestibular stimulation and that do not cause artifacts in the images. After completed these steps, 24 subjects were selected to perform three tasks: a purely visual (a flashing checkerboard in the center of the screen), a purely vestibular (with application of galvanic vestibular stimulation) and a simultaneous, presenting the visual and vestibular stimuli together. The purely visual stimulation showed activation of the primary and associative visual cortices, while the purely vestibular stimulation led to activation of areas involved in multimodal function of the vestibular system, such as the parieto-insular vestibular cortex, the inferior parietal lobe, the superior temporal gyrus, the precentral gyrus and the cerebellum. The simultaneous stimulation of visual and vestibular systems resulted in activation of the middle and inferior frontal gyri. In addition to the reciprocal inhibitory visualvestibular interaction pattern had been more evident during the simultaneous condition, it was observed that frontal regions (dorsomedial prefrontal cortex and superior frontal gyrus) are involved with the executive function processing when there is conflicting information of visual and vestibular systems.
43

Interação entre as áreas funcionais do sistema visual e do sistema vestibular: estudo com RMF e EGV

Justina, Hellen Mathei Della 21 February 2014 (has links)
CAPES, CNPq / O equilíbrio estático corporal é comandado por três sistemas sensoriais: o sistema vestibular, responsável pelas informações sobre a posição e os movimentos da cabeça; o sistema visual, que informa a posição espacial dos objetos em relação ao nosso corpo; e o sistema proprioceptivo, que controla a postura e a movimentação corporal. Estes três sistemas devem funcionar sempre em sintonia, caso contrário, o indivíduo apresentará problemas de equilíbrio. Dessa forma, é importante caracterizar as regiões corticais, bem como suas interações, envolvidas neste processo. Para isto, é necessário a utilização de técnicas de neuroimagem funcional, sendo a ressonância magnética funcional (RMf) uma das técnicas mais utilizadas neste campo nos dias de hoje. Entretanto, uma grande parte dos experimentos de RMf requer o uso de aparelhos eletrônicos para produzir estimulações somatosensoriais no corpo humano, onde a principal dificuldade é o seu ambiente hostil aos circuitos eletrônicos. A estimulação galvânica vestibular é um dos métodos mais utilizados para estimular o sistema vestibular. Esta consiste em fornecer uma corrente de baixa amplitude diretamente nas aferências vestibulares, a qual atua no disparo dos neurônios vestibulares primários atingindo principalmente as aferências otolíticas e as fibras dos canais semicirculares. O objetivo deste trabalho é analisar e avaliar as áreas cerebrais envolvidas com as estimulações visual e galvânica vestibular e suas interações, utilizando a técnica de RMf e um estimulador galvânico vestibular. Para tanto, como primeira etapa desta pesquisa, validou-se in vivo um estimulador galvânico vestibular. O estimulador elétrico não interferiu de forma significativa na qualidade das imagens de ressonância magnética e pode ser utilizado com segurança nos experimentos de RMf. Testes foram realizados para determinar um eletrodo suficientemente confortável para o voluntário durante a estimulação galvânica vestibular e que não causasse artefato nas imagens. Após estas etapas concluídas, 24 voluntários foram selecionados para realizarem três tarefas: uma puramente visual (um tabuleiro de xadrez piscante no centro da tela), uma puramente vestibular (pela aplicação da estimulação galvânica vestibular) e uma simultânea, com a apresentação em conjunto dos estímulos visual e vestibular. A estimulação puramente visual mostrou ativação dos córtices visual primário e associativo, enquanto que a estimulação puramente vestibular levou a ativação das principais áreas envolvidas com a função multimodal do sistema vestibular, como o córtex parietoinsular vestibular, o lóbulo parietal inferior, o giro temporal superior, o giro pré-central e o cerebelo. A estimulação simultânea dos sistemas visual e vestibular resultou na ativação dos giros frontal médio e inferior. Além do padrão de interação visual-vestibular inibitório recíproco ter sido mais evidente durante a condição simultânea, observou-se que as regiões frontais (córtex dorsomedial pré-frontal e giro frontal superior) estão envolvidas com o processamento da função executiva quando existem informações conflitantes dos sistemas visual e vestibular. / The static body equilibrium is controlled by three sensory systems: the vestibular system, responsible for informing the position and the movements of the head; the visual system, which informs the spatial objects position relative to the body; and the proprioceptive system, which controls posture and body movements. These three systems must always work in harmony, otherwise the individual will present balance problems. Thus, it is important to characterize the cortical regions, as well as their interactions, involved in this process. For this it is necessary to use functional neuroimaging techniques, the functional magnetic resonance imaging (fMRI) is one of the most used techniques in this field nowadays. However, a large fMRI experiments require the use of electronic devices for producing somatosensory stimulation in the human body, where the main difficulty is its hostile environment for electronic circuits. The galvanic vestibular stimulation is one of the most used methods to stimulate the vestibular system. This stimulation consist of applying a low current amplitude directly on vestibular afferents, which acts firing the primary vestibular neurons, affecting the otolithic afferents and the semicircular canals fibers. The objective of this work is to evaluate and analyze the brain areas involved with visual and galvanic vestibular stimulations and their interactions using fMRI. Therefore, as a first step of this research, a galvanic vestibular stimulator was validated in vivo. The electrical stimulator did not interfere in a significance way on magnetic resonance images quality and could be safely used in fMRI experiments. Tests were performed to select an electrode sufficiently comfortable for the volunteer during the galvanic vestibular stimulation and that do not cause artifacts in the images. After completed these steps, 24 subjects were selected to perform three tasks: a purely visual (a flashing checkerboard in the center of the screen), a purely vestibular (with application of galvanic vestibular stimulation) and a simultaneous, presenting the visual and vestibular stimuli together. The purely visual stimulation showed activation of the primary and associative visual cortices, while the purely vestibular stimulation led to activation of areas involved in multimodal function of the vestibular system, such as the parieto-insular vestibular cortex, the inferior parietal lobe, the superior temporal gyrus, the precentral gyrus and the cerebellum. The simultaneous stimulation of visual and vestibular systems resulted in activation of the middle and inferior frontal gyri. In addition to the reciprocal inhibitory visualvestibular interaction pattern had been more evident during the simultaneous condition, it was observed that frontal regions (dorsomedial prefrontal cortex and superior frontal gyrus) are involved with the executive function processing when there is conflicting information of visual and vestibular systems.
44

Estimulador galvânico vestibular para fMRI

Manczak, Tiago 30 July 2012 (has links)
Este trabalho apresenta o desenvolvimento de um estimulador galvânico vestibular para ser usado em experimentos de imageamento por ressonância magnética funcional (fMRI). Em experiências de fMRI é necessário a produção de estímulos somatossensoriais no paciente. Os estímulos devem ser sincronizados com a sequência de pulsos da fMRI. O estimulador foi dividido em circuitos analógicos (colocados dentro da sala do magneto) e circuitos digitais (sala de comando do sistema de MRI). A comunicação entre os circuitos é feita através de fibra óptica. Experimentos de fMRI realizados com voluntários demonstraram que o estimulador proposto é capaz de manter a sincronização com sistema de fMRI e pode ser usado para localizar as áreas do cérebro que são ativados pelo sistema vestibular. / This work presents the development of a galvanic vestibular stimulator to be used in functional magnetic resonance imaging experiments (fMRI). In fMRI experiments it is required the production of somatosensory stimuli in the patient must be sincronized with the fMRI pulse sequence. The stimulator circuits were divided in analog circuits (placed within the magnet room) and digital circuits (placed in the MRI command room). The communication between the circuits is made through optical fiber. fMRI experiments performed with volunteers demonstrated that the proposed stimulator is able to keep the sincronization with the MRI system and can be used to locate the brain areas that are activated by the vestibular system.
45

Estimulador galvânico vestibular para fMRI

Manczak, Tiago 30 July 2012 (has links)
Este trabalho apresenta o desenvolvimento de um estimulador galvânico vestibular para ser usado em experimentos de imageamento por ressonância magnética funcional (fMRI). Em experiências de fMRI é necessário a produção de estímulos somatossensoriais no paciente. Os estímulos devem ser sincronizados com a sequência de pulsos da fMRI. O estimulador foi dividido em circuitos analógicos (colocados dentro da sala do magneto) e circuitos digitais (sala de comando do sistema de MRI). A comunicação entre os circuitos é feita através de fibra óptica. Experimentos de fMRI realizados com voluntários demonstraram que o estimulador proposto é capaz de manter a sincronização com sistema de fMRI e pode ser usado para localizar as áreas do cérebro que são ativados pelo sistema vestibular. / This work presents the development of a galvanic vestibular stimulator to be used in functional magnetic resonance imaging experiments (fMRI). In fMRI experiments it is required the production of somatosensory stimuli in the patient must be sincronized with the fMRI pulse sequence. The stimulator circuits were divided in analog circuits (placed within the magnet room) and digital circuits (placed in the MRI command room). The communication between the circuits is made through optical fiber. fMRI experiments performed with volunteers demonstrated that the proposed stimulator is able to keep the sincronization with the MRI system and can be used to locate the brain areas that are activated by the vestibular system.
46

Vyšetření dynamické zrakové ostrosti u zdravých jedinců / Dynamic visual acuity testing in healthy individuals

Rezlerová, Pavlína January 2017 (has links)
In this study we examined dynamic visual acuity as a functional testing of the vestibulo- ocular reflex. Two groups were examined: 22 healthy seniors and 22 healthy young people as controls. We used two types of situations for testing: while walking on a treadmill at a speed of 2, 4 and 5 kmph, and with a subject's head passively moved in yaw and pitch plane. Visual acuity was measured with optotype charts (for the walking test it was a standard Snellen optotype chart at 6 m distance, for the test of head moves it was a Jaeger chart at 30 cm distance). The values obtained in these ways we related to values of a subject's static visual acuity, measured in the same conditions, just before the dynamic situations were examined. We found significant difference of dynamic visual acuity in senior group within each condition tested. We also found a significant decline as for difference of dynamic visual acuity in the senior group compared to young subjects - in the walking test at 4 and 5 kmph and in both head-moving conditions. These results indicate age-related impairment in function of vestibulo-ocular reflex. Based on our results, the test of passive head moves appears to be more suitable for ordinary clinical examination of dynamic visual acuity.
47

Galvanic vestibular stimulator for fMRI research / Estimulador galvânico vestibular para experimentos de fMRI

Rülander, Britta Angela 02 March 2016 (has links)
CAPES / This master thesis presents the further development of a galvanic vestibular stimulator for use in fMRI examinations developed in a previous thesis (MANCZAK, 2012). This thesis amends the GVS by circuits to measure feedback values and implements the stimulation circuit with digital components, such as a microcontroller and flyback integrated circuits. The microcontroller is used in order to control the current source and process the measured values. The communication between the PC, which allows user interaction through a graphical user interface, and the microcontroller is implemented through optical communication, which is defined by a communication protocol specification. The digital circuitry is designed to be placed within the MRI room, meeting the requirements imposed by strong magnetic fields and radio frequency pulses. The underlying hypothesis of the thesis is that the device can be placed within the MRI room without having a negative impact on the MRI image quality. Laboratory tests without the MRI confirmed the correct design of the galvanic vestibular stimulator.
48

Galvanic vestibular stimulator for fMRI research / Estimulador galvânico vestibular para experimentos de fMRI

Rülander, Britta Angela 02 March 2016 (has links)
CAPES / This master thesis presents the further development of a galvanic vestibular stimulator for use in fMRI examinations developed in a previous thesis (MANCZAK, 2012). This thesis amends the GVS by circuits to measure feedback values and implements the stimulation circuit with digital components, such as a microcontroller and flyback integrated circuits. The microcontroller is used in order to control the current source and process the measured values. The communication between the PC, which allows user interaction through a graphical user interface, and the microcontroller is implemented through optical communication, which is defined by a communication protocol specification. The digital circuitry is designed to be placed within the MRI room, meeting the requirements imposed by strong magnetic fields and radio frequency pulses. The underlying hypothesis of the thesis is that the device can be placed within the MRI room without having a negative impact on the MRI image quality. Laboratory tests without the MRI confirmed the correct design of the galvanic vestibular stimulator.
49

Persepsie van grondslagfase-onderwysers en ouers aangaande die effektiwiteit van vestibulere oefeninge om sensoriese en motoriese ontwikkeling te bevorder

Claassens, Heidi 01 1900 (has links)
Abstracts in Afrikaans and English / Inklusiewe onderrig ondersteun die insluiting van alle leerders met verskillende behoeftes en vaardighede in klaskamers, wat baie keer te groot, of te verskillend vir doeltreffende onderrig is. Beweging as deel van ‘n vroeë leerervaring is noodsaaklik vir optimale neurale ontwikkeling. Dit beïnvloed organisasie en stimuleer die spesifieke neurologiese sisteme nodig vir optimale funksionering en ontwikkeling van die brein. Sensoriese integrasie disfunksie word gesien as die wortel van baie leerprobleme. Die vestibulêre sisteem is direk verbind met die sensoriese en motoriese sisteme. ‘n Sensoriese integrasie disfunksie het ‘n duidelike invloed op die vestibulêre sisteem. Die vestibulêre sisteem het baie interkonneksies met baie dele in die brein, byvoorbeeld propriosepsie en die tassisteem. Doeltreffende funksionering van die sensoriese, motoriese en vestibulêre sisteme word verlang vir ‘n hoë vlak van prestasieverrigting in sport en akademie. Wanneer die vestibulêre sisteem gestimuleer word, het dit ‘n direkte positiewe invloed op die sensoriese en motoriese ontwikkeling van leerders. Die doel van hierdie studie was om te bepaal wat die persepsie van grondslagfase-onderwysers en ouers is oor die rol en voordele wat vestibulêre oefeninge te weeg kan bring in die motoriese en sensoriese ontwikkeling van leerders. Leerders in graad 1 van ‘n privaatskool, asook van grade 2 en 3 van ‘n plaasskool is gekies as deelnemers in die studie. Die keuse van leerders was op grond van die bereidwilligheid van hulle en hul ouers om aan die studie deel te neem. Leerders het ‘n vestibulêre oefenprogram drie maal per week gedoen vir die tydperk van agt weke. Observasie-vraelyste is deur onderwysers en ouers ingevul na afloop van die derde sessie elke week. Vir die vraelys het ouers en onderwysers gekyk na die verbetering in aandagspan, konsentrasie, luistervaardigheid, oogkontak, sosiale interaksie en samewerking. Onderhoude is met ouers en onderwysers gedoen na aanleiding van die observasievraelyste wat vir die agt weke voltooi is. Transkripsies van die onderhoude is gedoen en afleidings is gemaak deur analise van die observasie-vraelyste en die getranskribeerde onderhoude. Al ses die ontwikkelingsareas by beide skole het verbetering getoon oor die agt weke. Dit dui daarop dat vestibulêre oefeninge wel ‘n invloed op die sensoriese en motoriese ontwikkeling het. / Inclusive education promotes the inclusion of learners with different needs and capabilities in classes which are often too big and diverse for effective teaching. Movement as an early learning experience is necessary for optimal neural development. It influences organisation and stimulates the specific neurological systems required for optimal functioning and development of the brain. Sensory integrative dysfunction is believed to be at the root of many learning disorders. The vestibular system is directly connected with the sensory and motor systems. The vestibular system will be directly affected when a sensory integrations dysfunction presents. In fact, the vestibular system has many interconnections with almost every other part of the brain like proprioception and the tactile system. Proper functioning of the sensory, motor and vestibular systems is required for higher level performance in sport and academics. When the vestibular system is stimulated, it will result in a positive influence on the sensory and motor development of learners. The aim of this study is to determine the perceptions of foundation phase teachers and parents regarding the role or benefits of vestibular exercises in promoting learners’ motor and sensory development. Learners in Grade 1 of a private school and Grade 2 and 3 learners of a farm school in the northern Free State were selected as participants in the research. Learners were selected on the basis of the willingness of them and their parents to participate in the research. The participants did exercise sessions three times a week for thirty minutes over a period of eight weeks. Observation sheets were completed for all eight weeks, for the duration of the exercise program, by teachers and parents. These sheets were completed weekly after the third sessions in that week. The observation sheets listed concentration, attention span, listening, eye contact, cooperation, social interaction and self-esteem as developmental areas. Interviews were done after the period of eight weeks with the parents and teachers. The interviews conducted with both parties were taped and meticulously transcribed. This helped the researcher to get a better understanding of the study and to analise data and draw conclusions.All six areas of development showed improvement at both schools over the period of eight weeks. This indicates that stimulating the vestibular system promotes sensory and motor development. / Inclusive Education / M. Ed. (Inklusiewe Onderwys)

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