A functioning prototype test motor with Hall-sensor feedback has been built, and the test results show that the motor performance in terms of speed ripple is well within the specified demands. The temperature demands however, have not been fully met. The minimum operating temperature of the sensor was specified to -55◦C by Saab, and the sensors found on the market has a minimum operating temperature of -40◦C. There was also an operation error, the reason of which could either be failure of the drive unit to deliver enough current, or the stator magnetic field strength being too strong for the sensors to reliably detect the rotor magnets when a sufficiently strong current is run through the stator windings. For the purpose of investigating this error it is proposed to conduct tests with a drive unit that can deliver currents over 5 A. / SWE Demo

Det har tidigare rapporterats att icke-stammande personer har en tydlig vänstersidig cerebral lateralisering vad gäller talmotoriken, vilket visas genom ökad högersidig aktivering i läppmuskulaturen. Personer med stamning har å andra sidan föreslagits ha ett vänstersidigt eller bilateralt aktiveringsmönster av talmuskulaturen. Detta antas vara en av orsakerna till stamning. Testdeltagarna i aktuell studie bestod av 11 stammande och 13 matchade icke-stammande vuxna. Uppgifterna bestod av ordrepetition, ordgenerering samt att puta med läpparna. EMG-aktivitet från musklerna orbicularis oris och depressor labii inferior registrerades med elektroder på höger och vänster sida av läppmuskulaturen. Syftet med aktuell studie var att undersöka eventuell skillnad i läppasymmetri mellan stammande och icke-stammande vuxna personer. Resultatet kunde inte påvisa signifikanta gruppskillnader i grad av muskelaktivering för läppmuskulaturen. Båda grupperna uppvisade tvärtemot förväntan en nästintill bilateral aktivitet. En tendens till positiv korrelation, om än inte statistiskt signifikant, kunde observeras mellan grad av uppvisad stamning och något mer högersidig muskelaktivering.

Relatively little is known about the role of the basal ganglia and their pathways in human deglutition. Deep Brain Stimulation (DBS) is a treatment for Parkinson Disease (PD) that stimulates the subthalamic nuclei and affords us a model for examining deglutition in humans with known impairment of the basal ganglia. The purpose of this study was to examine the effects of DBS in the ON versus Off conditions on the oral and pharyngeal stages of deglutition in participants with PD. It was hypothesized that DBS in the ON condition would yield improvement in the following dependent variables: oral total composite score, pharyngeal total composite score, pharyngeal transit time, and maximal hyoid bone excursion. Statistically significant differences (improvement) were found for the pharyngeal composite score and pharyngeal transit time in the DBS ON condition. Findings of this study demonstrated that DBS in the ON condition helps to alleviate some of the bradykinesia and hypokinesia associated with PD on the pharyngeal stage of deglutition, but not the oral stage. These findings suggest that Parkinsonian swallowing dysfunction is not solely related to nigrostriatal dopamine deficiency which is purported to be the primary means of DBS alleviation of motor signs. Rather, it may be due to an additional non-dopamine related system of deglutition found in the brainstem.

This thesis provides new insights about how the brain controls skilled movements, through the study of limb apraxia in two major neurological disorders: Stroke and Corticobasal Syndrome (CBS). Limb apraxia is a cognitive-motor deficit characterized by impairment in the performance of skilled movement. The Conceptual-Production systems model, used as framework in this thesis, proposes that skilled movement is under the control of three systems: a sensory/perceptual system, a conceptual system and a production system. Deficits in any of these systems produce limb apraxia, and depending on which system is affected, a distinct pattern of apraxia emerges. This information processing approach was used to evaluate performance levels, study brain asymmetries and discern patterns of deficits in each population. In addition, longitudinal assessments in sample subsets revealed patterns of recovery after stroke and of progression in CBS. The first study examined acute-subacute and chronic stroke patients with left (LHD) and right hemisphere damage (RHD) for their ability to pantomime and imitate transitive and intransitive gestures. The results indicated that LHD and acute-subacute were more severely impaired. Concurrent deficits in pantomime and imitation were most common, especially after LHD. Since acute-subacute patients were more severely impaired, in the absence of any therapies, it is likely that some degree of recovery occurs over time. The second study study examined longitudinal recovery in a series of transitive gestures tasks among stroke patients and indicated that patients significantly recovered in all tasks, except in Action Identification, a conceptual apraxia task which probes knowledge of actions. Finally, two comparative studies were conducted in CBS, a neurodegenerative disorder in which apraxia is common, making this one of the first studies that evaluated patient performance on a complete limb apraxia battery. The first study found that patients were often impaired on all gesture production tasks, while conceptual knowledge of gestures and tools was usually preserved. A case series constituted the second study, which documented the progression of apraxia in CBS demonstrating that, while deficits in gesture production usually are present at first examination, deficits in conceptual knowledge are infrequent and in many cases do not develop at all. Study limitations were discussed and it was suggested that future research should expand on our findings for recovery in stroke and progression in CBS.

This dissertation looks at motor control in speech production. Two specific questions emerging from the speech motor control literature are studied: the question of articulatory versus acoustic motor control targets, and the question of whether prosodic linguistic variables are controlled in the same way as segmental linguistic variables. In the first study, I test the utility of whispered speech as a tool for addressing the question of articulatory or acoustic motor control targets. Research has been done probing both sides of this question. The case for articulatory specifications is developed in depth in the Articulatory Phonology framework of Haskins researchers (eg. Browman & Goldstein 2000), based on the task-dynamic model of control presented by Saltzman & Kelso (1987). The case for acoustic specifications is developed in the work of Perkell and others (eg Perkell, Matthies, Svirsky & Jordan 1993, Guenther, Espy-Wilson, Boyce, Matthies, Zandipour & Perkell 1999, Perkell, Guenther, Lane, Matthies, Perrier, Vick,Wilhelms-Tricarico & Zandipour 2000). It has also been suggested that some productions are governed by articulatory targets while others are governed by acoustic targets (Ladefoged 2005). This study involves two experiments. In the first, I make endoscopic video recordings of the larynx during the production of phonological voicing contrasts in normal and whispered speech. I discovered that the glottal aperture differences between voiced obstruents (ie, /d) and voiceless obstruents (ie, /t) in normal speech was preserved in whispered speech. Of particular interest was the observation that phonologically voiced obstruents tended to exhibit a narrower glottal aperture in whisper than vowels, which are also phonologically voiced. This suggests that the motor control targets of voicing is different for vowels than for voiced obstruents. A perceptual experiment on the speech material elicited in the endoscopic recordings elicited judgements to see whether listeners could discriminate phonological voicing in whisper, in the absence of non-laryngeal cues such as duration. I found that perceptual discrimination in whisper, while lower than that for normal speech, was significantly above chance. Together, the perceptual and the production data suggest that whispered speech removes neither the acoustic nor the articulatory distinction between phonologically voiced and voiceless segments. Whisper is therefore not a useful tool for probing the question of articulatory versus acoustic motor control targets. In the second study, I look at the multiple parameters contributing to relative prominence, to see whether they are controlled in a qualitatively similar way to the parameters observed in bite block studies to contribute to labial closure or vowel height. I vary prominence by eliciting nuclear accents with a contrastive and a non-contrastive reading. Prominence in this manipulation is found to be signalled by f0 peak, accented syllable duration, and peak amplitude, but not by vowel de-centralization or spectral tilt. I manipulate the contribution of f0 in two ways. The first is by eliciting the contrastive and non-contrastive readings in questions rather than statements. This reduces the f0 difference between the two readings. The second is by eliciting the contrastive and non-contrastive readings in whispered speech, thus removing the acoustic f0 information entirely. In the first manipulation, I find that the contributions of both duration and amplitude to signalling contrast are reduced in parallel with the f0 contribution. This is a qualitatively different behaviour from all other motor control studies; generally, when one variable is manipulated, others either act to compensate or do not react at all. It would seem, then, that this prosodic variable is controlled in a different manner from other speech motor targets that have been examined. In the whisper manipulation, I find no response in duration or amplitude to the manipulation of f0. This result suggests that, like in the endoscopy study, perhaps whisper is not an effective means of perturbing laryngeal articulations.

This thesis investigates how adults, infants, and children use visual information to control reaching movements. To do this, the kinematics of a reaching movement were recorded using a 6 camera motion tracking system. Adult reaching movements were investigated in three different experiments. The first experiment looked at the effect of visual information about the reach space and the target on reaching movements. Adult reaches are significantly affected by removal of visual information about the reach space and the target, e.g. peak speed decreases as distance information is occluded. Adult reaching movements are also affected by the length of the delay between viewing an object and then reaching for it in complete darkness. Experiment 2 reveals that there is a linear increase in movement duration, decrease in peak speed, and increase in maximum grip aperture with increasing temporal delay. This is due to the decay of dorsal visual information. Experiment 3 found that a cautious reaching movement can be defined as a reach where duration increases, average speed decreases, and peak timing is proportionally earlier in the reach. The three developmental experiments investigated the changes in reaching in infancy, in typically developing 5-year-old children, and in children with Williams syndrome (WS). Between 9 and 16 months of age, infants develop better coordination of reaching movements. Improved dark reaching behaviour in 16-month-olds may be associated with more mature processing in the dorsal visual stream. Reaching movements in 5-year-old children are straighter and faster than infant reaches but behaviour is not yet stereotyped like adults. WS children generate reaches that are slower and incorporate more movement units than 5-year-old children, and WS behaviour may reflect poor processing of dorsal visual information rather than poor control of arm movement.

Reaching is a fundamental movement and has been studied widely in the motor control area. To my knowledge no one has directly compared the planning and kinematic characteristics of these two movements. These different definitions of reaching movements may also explain why researchers have reported different results when examining reaching movements of individuals with Autism Spectrum Disorder (ASD). The present study designed three movement types to examine how people with and without ASD plan and execute three different types of reaching movements. The results revealed that typically developing (TD) participants moved faster compared to ASD participants in three dimensional movements, but not in one dimensional and two dimensional movements. Based on the above results it is proposed that the observed difference in movement control resulted from a preference for different sensory feedback for on-line control of limb movements. / October 2015

A hanseniase e uma doenca endemica no Brasil sendo considerado um problema de saude publica. A hanseniase causa acometimentos oculares, cutaneos, sistemicos e nervosos, sendo este ultimo o mais importante, pois provoca alteracoes de sensibilidade e propriocepcao, que podem afetar o controle da postura. O objetivo principal deste estudo e descrever o controle postural de sujeitos portadores de hanseniase e compara-los com sujeitos saudaveis. Para tanto, tambem serao mensuradas algumas respostas sensorio-motoras possivelmente relacionadas ao controle postural destes sujeitos. Foi avaliado o controle postural por meio do Teste Clinico de Interacao Sensorial no Equilibrio modificado utilizando-se uma plataforma de forca e do BESTest, Balance Evaluation Systems Tests, uma medida funcional do equilibrio. Quanto as respostas sensorio-motoras, foram avaliados os reflexos tendinosos, a forca muscular, a palpacao de dois nervos do membro inferior, a propriocepcao, a sensibilidade cutanea, a acuidade visual, em todos os sujeitos, e o grau de incapacidades fisicas apenas nos sujeitos portadores de hanseniase. De forma geral, todas as respostas sensorio-motoras dos portadores de hanseniase estao prejudicadas. O desempenho no BESTest indica que os portadores de hanseniase apresentam dificuldades em controlar o equilibrio em tarefas tipicas das atividades da vida diaria. O desempenho nas tarefas de equilibrio quantificado pela posturografia indica que os portadores de hanseniase apresentam dificuldades em controlar o equilibrio na postura ereta quieta sem ou com manipulacao da informacao sensorial. Os resultados reportados neste trabalho mostram pela primeira vez que portadores de hanseniase possuem deficits no controle postural relevantes para a manutencao do equilibrio e para execucao de outras tarefas comuns da vida diaria. Estes resultados sugerem que portadores de hanseniase devem receber auxilio especial para que estes deficits possam ser diminuidos / Hansen\'s disease is an endemic disease in Brazil and it is considered a public health problem. The Hansen\'s disease causes eye, cutaneous, systemic, and nervous problems; being the latter the most important hence affects the sensibility and proprioception and possibly can affect postural control. The main goal of this study is to describe the postural control of individuals with Hansen\'s disease and compare them to healthy individuals. For such, it will also be measured sensory-motor responses possibly related to the postural control of these individuals. The postural control was evaluated employing a modified version of the Clinical Test of Sensory Interaction and Balance using a force plate and the BESTest, Balance Evaluation Systems Tests, a functional measure of the postural control. In regard to the sensory-motor responses, it was evaluated the tendinous reflex, muscle force, palpation of two nerves of the lower limb, proprioception, cutaneous sensibility, visual acuity, in all subjects, and the degree of physical incapacity only of individuals with Hansen\'s disease. In general, all the sensory-motor responses of the individuals with hanseniase are deteriorated. The performance in the BESTest suggests that individuals with Hansen\'s disease have problems in controlling their posture in typical daily living tasks. The performance in the postural control tasks measured by posturography also suggests that the individuals with Hansen\'s disease have problems in controlling their posture with or without the manipulation of the sensory information. These results show by the first time that individuals with Hansen\'s disease have significant postural control deficits that impair their ability to maintain their upright posture and to execute common daily living tasks. These results suggest that individuals with Hansen\'s disease must receive special attention in order to reduce these deficits

O presente estudo teve como objetivo avaliar o efeito da expectativa na reorganização de aspectos espaciais e temporais em ações interceptativas. O estudo foi conduzido em dois experimentos, nos quais os participantes interceptaram manualmente um alvo móvel virtual em situações com diferentes probabilidades de mudança de trajetória/velocidade de deslocamento do alvo. Em ambos os experimentos foi realizada a comparação entre um grupo que recebeu informação verbal sobre a probabilidade de mudança de trajetória/velocidade (PR), e outro que não recebeu informação (SI) sobre as características probabilísticas da tarefa. Os resultados do experimento com mudança de trajetória indicaram que, além da reorganização na dimensão espacial ocorrer de maneira gradativa, as ações interceptativas parecem ter sido controladas por um mecanismo preditivo que é atualizado ao longo do tempo por informação visual. Em ambos os experimentos foi mostrado que a probabilidade do contexto influenciou as características espaciais e temporais da reorganização do movimento. Contudo, essa influência ocorreu somente no fim de uma série de tentativas. Este resultado, em conjunto com a ausência de diferença em aspectos cinemáticos e de desempenho entre os grupos experimentais, sugere que a expectativa de deslocamento futuro do alvo foi criada em função das tentativas iniciais de uma série e não pela informação verbal / The aim of the present study was to evaluate the effect of expectancy on reorganization of spatial and temporal dimensions in interceptive actions. The study was conducted through two experiments in which participants were to manually intercept a virtual moving target with different probabilities of target trajectory/velocity shift. Comparison between a group that received verbal information concerning probability of target trajectory/velocity shift (PR), and another group that did not receive that information (SI) was made in both experiments. Results of the experiment on target trajectory shift showed that, in addition to gradual movement reorganization in the spatial dimension, interceptive actions were controlled by a predictive mechanism which seemed to be continuously updated by visual information. Of main interest, it was shown that in both experiments probability of target trajectory/velocity change influenced the spatial and temporal characteristics of movement reorganization. However, this influence occurred only at the end of a series of trials. The same effect was observed in the experiment on target velocity shift. This result, adjoined with the absence of difference in kinematic and performance aspects between experimental groups, suggests that expectancy about future target displacement was created by the initial trials of a series and not by verbal information on probability of target trajectory/velocity shift

A análise do chute através de técnicas biomecânicas pode auxiliar na compreensão do comportamento e organização do sistema motor. Ao identificar a predominância, emergência ou variabilidade de um padrão de movimento, deve-se considerar a interação de elementos internos e externos ao indivíduo, seja o ambiente onde está sendo executada a ação, as características que envolvem a tarefa ou as particularidades do organismo do executante. O objetivo deste trabalho foi analisar e comparar o padrão de movimento e o desempenho da habilidade motora chutar, a um alvo, em duas condições: bola parada e bola em movimento. Com o propósito de detectar a influência da faixa etária na execução desta tarefa, participaram deste estudo 10 crianças divididas em dois grupos: G1 (8 a 9 anos) e o G2 (12 a 13 anos). Cada criança realizou 10 chutes a um alvo em ambas as condições. As tentativas foram capturadas por duas câmeras de alta velocidade e foram obtidos dados referentes ao desempenho, variabilidade, coordenação e amplitude do movimento. A análise estatística detectou ajustes na coordenação e amplitude do movimento além de um aumento da variabilidade na condição da bola em movimento. Em relação à idade, foram encontradas diferenças estatisticamente significantes na velocidade do pé. Os resultados demonstraram que os grupos etários estudados apresentaram ajustes similares na coodenação do movimento. A condição da bola provocou adaptações no padrão de movimento, entretanto, apesar do aumento nos níveis de variabilidade, não exerceu influência no desempenho do chutar / The analysis of kicking through biomechanics techniques can help the comprehension of behavior and motor system organization. In order to identify the predominance, emergence, or variability of a moving pattern, is imperative to consider the interactions between internal and external elements to the individual, such as the environment where the action is executed, characteristics that are intrinsic to the task or any individual particularity. The aim of the present work was to analyze and compare the performance and movement pattern of the kick realized by children to a target, in two different conditions: stationary and moving ball. To enable us to detect the age influence on the execution of the given task, the experimental group comprised 10 children from different ages: group 1 (G1) children from 8 to 9 years old and group 2 (G2) children from 12 to 13 years old. Each participant performed 10 kicks to the target in both conditions. Attempts were captured by two high speed cameras and were obtained data to analyze performance, variability, coordination and range of motion. Statistical analysis showed adjustments in coordination and range of motion, besides an increase of variability in the condition of moving ball in relation to the stationary ball condition. Regarding the age, it was found differences statistically significant only in the foot velocity. The results showed that the age groups studied had similar adjustments in movement coordination. The moving ball condition led to adjustments in the movement pattern, however, despite the increase in the variability, the performance was not different in relation to the stationary ball condition