Peripersonal (reachable) and extrapersonal (beyond reach) space is linked to hand perception. Using a tool to reach farther than normal recalibrates previously unreachable space as peripersonal, evidenced by Intraparietal Sulcus (IPS) activity related to hand perception and lateral biases during line bisection. The current study looked at the role of a visual connection between the hand and body in the ability to manipulate objects within the extended area of reach. In an immersive virtual environment, participants bisected lines using a connected hand (via arm), a disconnected hand, or a floating dot. A rightward shift in bisection was seen only for the dot condition for far lines, indicating that it was the only "tool" incapable of extending peripersonal space.

Peripersonal (reachable) and extrapersonal (beyond reach) space is linked to hand perception. Using a tool to reach farther than normal recalibrates previously unreachable space as peripersonal, evidenced by Intraparietal Sulcus (IPS) activity related to hand perception and lateral biases during line bisection. The current study looked at the role of a visual connection between the hand and body in the ability to manipulate objects within the extended area of reach. In an immersive virtual environment, participants bisected lines using a connected hand (via arm), a disconnected hand, or a floating dot. A rightward shift in bisection was seen only for the dot condition for far lines, indicating that it was the only "tool" incapable of extending peripersonal space.

Background: The world of sports possesses a lot of knowledge when it comes to leadarship and coaching. Coaching as a term is relatively new to the business industry and something that is up and coming among alot of companies. Leadership and coaching are two terms that can be combined with each other both in sports and in the business industry. Objectives: This study aims to compare leadership in sports and in the business industry. The purpose is to see if they can learn from each other and how they define the term leadership. Method: Interviews were chosen as a method in this study. Six individual interviews were performed and there were three leaders from the business industry and three leaders from the world of sport participating in the study. The criteria to be a part of the study was that they had a couple of year's experience from working with leadership. Results: The result shows that leaders in the business industry work were similar as the leaders in the world of sports. There are many things that they think they can learn from each other. One of the things is how to work with setting up goals. In the business industry they work a lot with goals based on result and in the world of sports they work wih goals based on performance. This is one thing that the leaders in the business industry can learn from sports. The results show that leadership is about engaging another human being to work hard and do their best. In both worlds you need to be able to lead by example and adjust your leadership to the situation.

Motor noise and redundancy are vexing issues in motor control; yet their understanding provides great insights on underlying control mechanisms that govern movement. They provide glimpses into how the nervous system organizes and regulates movement within the motor control system. Understand of motor control could spur new advances in motor control could lead to better development of rehabilitation process and technology to counteract debilitating affects of neuromuscular disorders and motor readjustment with prostheses. However, before such process and technology could be developed and adapted for clinical use, a deeper understanding of motor control is needed to unravel the neural roadmap that regulates and generates movement. New theory of motor control could precipitate the development of more robust control mechanisms for robotic-human interaction. This work aims at expanding a more rigorous analytical and mathematical framework to understand how these control mechanisms reconcile redundancy and stochastic noise in human motor control. / text

Movement is essential to human life because it provides us with the freedom of mobility and the power to affect our surroundings. Moreover, movements are vital to communication: from hand and finger movements when writing, mouth and throat movements when speaking, to painting, dancing, and other forms of artistic self expression. As people grow and experience new environments, adaptively maintaining the accuracy of movements is a critical function of the motor system. In this dissertation, I explore the key mechanisms that underlie the adaptability of simple visually guided reaching movements. I specifically focus on two key facets of this adaptability: how motor learning rate can be predicted by motor variability and how motor learning affects the mechanisms which underlie movement planning. Inspired by reinforcement learning, I hypothesized that greater amounts of motor variability aligned with a task will produce more effective exploration, leading to faster learning rates. I discovered that this relationship predicts person-to-person and task-to-task differences in learning rate for both reward-based and error-based learning tasks. Moreover, I found that the motor system actively and enduringly reshapes motor output variability, aligning it with a task to improve learning. These results indicate that the structure of motor variability is an activelyregulated, critical feature of the motor system which plays a fundamental role in determining motor learning ability. Combining prominent theories in motor control, I created a model which describes the planning of visually guided reaching movements. This model computes a weighted average of two independent feature-based motor plans: one based on the goal location of a movement, and the other based on an intended movement vector. Employing this model to characterize the generalization of adaptation to movements and movement sequences, I find that both features, movement vector and goal location, contribute significantly to movement planning, and that each feature is remapped by motor adaptation. My results show that multiple features contribute to the planning of both point-to-point and sequential reaching movements. Moreover, a computational model which is based on the remapping of multiple features accurately predicts how visuomotor adaptation affects the planning of movement sequences. / Engineering and Applied Sciences

Trial-to-trial variability in human movement is often overlooked and averaged out, but useful information can be gleaned on the brain’s control of variability. A task can be defined by a function specifying a solution manifold along which all task variable combinations will lead to goal success – the Goal-Equivalent Manifold (GEM). We selected a reaching task with variables reach Distance (D) and reach Time (T). Two GEMs were selected: a constant D/T and constant D×T. Subjects had no knowledge of the goal prior to the experiments and were instructed only to minimize error. Subjects learned the generalized tasks by reducing errors and consolidated learning from one day to the next, generalized learning from the D×T to the D/T GEM, and had interference of learning from the D/T to the D×T GEM. Variability was structured along each GEM significantly more than perpendicular to it. Deviations resulting in errors were corrected significantly more quickly than any other deviation. Our results indicate that subjects can learn generalized reaching tasks, and the brain exploits redundancy in those tasks. / text

Maternal consumption of alcohol during pregnancy can induce a range of behavioral and cognitive deficits in offspring, which are collectively termed Fetal Alcohol Spectrum Disorders (FASD). There are significant delays in motor development and sensory-motor skills in children with FASD, but the underlying neurobiological mechanisms of these deficits are poorly understood. The goal of this research project is to test the hypothesis that the Kinesiological Instrument for Normal and Altered Reaching Movements (KINARM) will serve as an effective tool for identifying and measuring specific, neurologically-based motor deficits in children with FASD. These deficits were revealed through investigation of multi-joint upper limb movements during the performance of sensory-motor tasks. Children (31 FASD; 83 controls, aged 5 to 18 years, male and female) performed: (1) a visually-guided reaching task with fingertip feedback only; and children (31 FASD; 49 controls, aged 5 to 18 years, male and female) performed: (2) an arm position-matching task in the absence of visual feedback. Children with FASD differed significantly from controls in many reaching task outcome measures, specifically those related to the initial motor response and corrective responses. In particular, large effect sizes were observed for outcome measures related to the first (initial) movement (corresponding to feedforward control; e.g., direction error; distance error), as well as for those measures related to corrective responses (corresponding to feedback control; e.g., difference between minimum and maximum hand speeds; number of speed peaks during movement). In the position-matching task, children with FASD constricted the spatial workspace of the subject-controlled arm relative to the robot-controlled arm, in the horizontal axis. There was also observed a systematic shift between the subject- and robot-controlled arms in the XY end position, resulting in significant error. Additionally, children with FASD exhibited significantly increased trial-to-trial variability for final hand position of the subject-controlled arm, over all targets, and for which large effect sizes were observed. The results suggest that children with FASD have difficulty integrating sensory information into planned motor movements. The KINARM is a promising research tool that may be used to assess motor control deficits in children affected by prenatal exposure to alcohol. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2010-09-02 15:10:25.653

abstract: Adapting to one novel condition of a motor task has been shown to generalize to other naïve conditions (i.e., motor generalization). In contrast, learning one task affects the proficiency of another task that is altogether different (i.e. motor transfer). Much more is known about motor generalization than about motor transfer, despite of decades of behavioral evidence. Moreover, motor generalization is studied as a probe to understanding how movements in any novel situations are affected by previous experiences. Thus, one could assume that mechanisms underlying transfer from trained to untrained tasks may be same as the ones known to be underlying motor generalization. However, the direct relationship between transfer and generalization has not yet been shown, thereby limiting the assumption that transfer and generalization rely on the same mechanisms. The purpose of this study was to test whether there is a relationship between motor generalization and motor transfer. To date, ten healthy young adult subjects were scored on their motor generalization ability and motor transfer ability on various upper extremity tasks. Although our current sample size is too small to clearly identify whether there is a relationship between generalization and transfer, Pearson product-moment correlation results and a priori power analysis suggest that a significant relationship will be observed with an increased sample size by 30%. If so, this would suggest that the mechanisms of transfer may be similar to those of motor generalization. / Dissertation/Thesis / Masters Thesis Biomedical Engineering 2018

Made available in DSpace on 2014-06-11T19:22:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-03Bitstream added on 2014-06-13T19:08:26Z : No. of bitstreams: 1 diz_mcr_me_rcla.pdf: 414450 bytes, checksum: c04f6dde9fc1d2669655f18545ed86ab (MD5) / Universidade Estadual Paulista (UNESP) / A perseveração motora tem sido recentemente usada para interpretar a canônica tarefa “A não B” de Piaget. Nesta tarefa, as crianças observam o experimentador esconde um brinquedo em uma localização “A”, um atraso é imposto, e então a criança é encorajada a alcançar. Para as tentativas em A, as crianças tipicamente alcançam para A, onde o objeto foi escondido. Depois de esconder várias vezes e alcançar sucessivamente para A, o experimentador esconde o brinquedo em uma segunda localização, “B”, sob condições idênticas ao lado A. Tipicamente por volta do 9 meses de idade, crianças, mesmo olhando esse jogo de esconder e procurar volta a alcançar o brinquedo A depois de o experimentador ter dado a dica no brinquedo B. Explicações iniciais do erro “A não B” são retratados como um problema de codificação do novo local, fragilidade da memória para o novo local, ou a ação repetida. Por outro lado, as crianças perseveram menos nas tentativas em B se os locais A e B são distintos visualmente. Entretanto observamos que a informação visual na tarefa “A não B” é importante para o aparecimento ou não da perseveração motora. A proposta deste estudo foi verificar se crianças com deficiência visual perseveram ou não na tarefa modificada Pigetiana de alcance “A não B”, identificar o relacionamento das diferentes propriedades do objeto na taxa de perseverativa, identificar o relacionamento entre a orientação da cabeça e o alcançar durante sua performance, bem como o padrão cinemático do alcançar. Dez bebês com deficiência visual, baixa visão, entre 1 a 4 anos de idade foram autorizados por seus pais para participarem do estudo. As crianças foram avaliadas em duas condições: luminosa e sonora. Enquanto realizaram a tarefa “A não B”, todos os participantes foram filmados por três câmeras. Os resultados revelaram que o grupo... / Motor perseveration has recently been used to interpret the canonical Piaget's “A not B” task. In this task, the infants watch as the researcher hides a toy in a location “A”, a delay is imposed, and then the infants are allowed to reach. On these A trials, infants typically reach to A, to where the object was hidden. After several hidings and successive reaches to A, the researcher hides the toy in a second location, “B”, under identical conditions of the location A. Typically, around the age of nine months, infants, even after watching these “hide and search” games, return to reach for the “A” toy after being cued to reach for the “B” toy. Initial explanations for the “A not B” error portrayed it as a problem of encoding the new location, fragility of memory for the new location, or repeated action. On the other hand, infants are less likely to perseverate on attempts to B if the A and B locations are visually distinct. However, we observed that visual information in the “A not B” task is important to the emergence or not of the motor perseveration. The purpose of this study was to determine whether or not children that that have visual deficiency perseverate in a modified Piagetian “A not B” reaching task, to identify the relationship between different characteristics of the object and motor perseveration rate, and also, to identify the relationship between head orientation and reaching during their performance, as well as, the reaching kinematics pattern. Ten visually impaired children, low vision, among age of 1 and 4 years, were authorized by their parents to take part in this study. The children were measured in two conditions: luminous and sonorous. While performing the “A not B” sand box task, all participants were videotaped with three cameras. A section experiment showed results confirming that the group only perseverated under... (Complete abstract click electronic access below)

O movimento de alcançar e de pegar objetos é amplamente utilizado nas atividades diárias. Desta forma, diversos estudos têm analisado e descrito este padrão de movimento em função de diferentes aspectos que influenciam seu controle. Da mesma forma, o movimento de andar é uma habilidade fundamental nas atividades diárias e tem sido estudado e descrito amplamente na literatura. Entretanto, pouco se sabe sobre quais são as alterações que ocorrem nessas habilidades motoras quando elas são combinadas. A realização combinada de habilidades motoras (ex., andar e pegar um objeto) está muito presente no dia a dia das pessoas, mas o entendimento do controle desse tipo de tarefa combinada ainda não foi elucidado. Adicionalmente, ainda não está claro quais são as modificações que ocorrem nestes movimentos em função do processo de envelhecimento e do histórico de quedas recentes em idosos. Desta forma, três estudos foram conduzidos para investigar o desempenho motor de adultos jovens e idosos com e sem histórico de quedas na marcha combinada com o movimento de preensão em função do nível de dificuldade da tarefa manual. O primeiro estudo investigou o desempenho motor dos adultos jovens na marcha combinada com o movimento de preensão. O segundo estudo comparou o desempenho motor entre idosos com e sem histórico de quedas na marcha combinada com o movimento de preensão. Ainda, o terceiro estudo comparou o padrão de coordenação entre idosos (com e sem histórico de quedas) e adultos jovens na marcha combinada com o movimento de preensão. Participaram desta tese, 45 indivíduos distribuídos em três grupos (n=15): adultos jovens, idosos sem histórico de quedas e idosos com histórico de quedas. Os indivíduos foram convidados a alcançar e pegar um objeto em duas tarefas (manutenção da postura ereta e marcha) e para cada uma, seis condições experimentais foram realizadas com diferentes níveis de dificuldade. Para analisar o movimento de preensão, movimentos do corpo todo e os parâmetros espaço-temporais da marcha, um sistema tridimensional de análise de movimento foi utilizado. Modificações na marcha e no movimento de preensão foram identificados quando combinados, especialmente para as condições mais desafiadoras da tarefa manual. A adição da tarefa de pegar o objeto provocou uma adaptação na marcha, pois os participantes adotaram uma estratégia mais conservadora para aumentar a estabilidade dinâmica durante a fase de aproximação. Assim é possível sugerir que o movimento de preensão foi sobreposto ao da marcha, embora as adaptações no comportamento motor sejam globais, pois ambos os padrões motores (marcha e preensão) foram modificados para realizar com sucesso a tarefa em função dos diferentes níveis de dificuldade da tarefa manual. Os idosos com histórico de quedas apresentaram um desempenho motor inferior aos idosos sem histórico de quedas na marcha combinada com o movimento de preensão, como por exemplo, redução na velocidade do passo, aumento na duração do passo, redução na velocidade do punho e na abertura entre os dedos. Além disso, os idosos com histórico de quedas apresentaram maior redução na velocidade do COM AP em comparação com os idosos sem histórico de quedas. Assim, o paradigma de tarefas combinadas desenvolvido no presente estudo identificou mudanças nas estratégias de controle motor em idosos caidores, sendo que estas alterações foram ainda mais evidenciadas nas condições manuais mais difíceis. Ainda, a adição da tarefa de pegar o objeto na marcha modificou o padrão de coordenação entre membros superiores e inferiores para os movimentos de flexão/extensão e abdução/adução. Assim, para os movimentos de flexão e extensão, um padrão mais em fase e menos fora de fase foi identificado na condição de preensão comparado com a marcha livre quando o ombro direito foi analisado em relação ao ombro esquerdo e quadril direito. Para os movimentos de abdução e adução, quando o movimento de ombro direito foi analisado em relação ao ombro esquerdo e quadril direito, foi observado um padrão menos em fase. Além disso, um padrão menos fora de fase foi observado para os acoplamentos entre ombro direito-ombro esquerdo e ombro direito-quadril esquerdo. Entretanto, estas mudanças no padrão de coordenação não foram afetadas pelo nível de dificuldade manual. Este resultado sugere que as mudanças no padrão de coordenação são mais globais, enquanto mudanças específicas no movimento de membro superior são necessárias para acomodar as diferentes demandas da tarefa manual. Finalmente, idosos com histórico de quedas apresentaram um padrão diferente de coordenação quando comparados com os adultos jovens, como por exemplo, um padrão mais fora de fase para o acoplamento entre ombro direito e quadril direito e um padrão menos fora de fase para o acoplamento entre ombro direito e quadril esquerdo na marcha combinada com o movimento de preensão. Desta forma, parece que os idosos com histórico de quedas desacoplam a tarefa da marcha combinada com o movimento de preensão, diferentes dos adultos jovens e idosos sem histórico de quedas. / Reaching-to-grasping an object is widely used in daily activities. Many studies have analyzed and described this movement pattern considering different aspects that influence how it is controlled. Likewise, walking is a fundamental skill in daily activities and has been studied and described widely in the literature. However, little is known about what are the changes that occur in these motor skills when they are combined. The combined performance of motor skills (e.g. walk and grasp an object) is very common in daily life activities, but the understanding of the control mechanisms of this type of task is lacking. In addition, it is not clear what are the changes that occur in these movements due to aging and changes in balance control as observed in older adults with history of falls. Thus, three studies were designed to investigate the motor performance of young adults and older adults with and without history of falls during walking combined with prehension. The first study investigated motor performance of young adults while performing the combined task of walk and prehension at different levels of difficulty of the manual task. The second study investigated the same combined task with different levels of manual task difficulty in older adults with and without history of falls. Yet, the third study investigated the interlimb coordination pattern in young and older adults with and without history of falls during the combined task of walking and prehension with different levels of manual task difficulty. Forty-five individuals, distributed in three groups (young adults; older adults without history of falls; older adults with history of falls), participated in this study. They performed the reach-to-grasp movement in two tasks (upright stance and gait) involving six experimental condition with different levels of manual difficulty. To analyze prehension, body movements and spatio-temporal gait parameters, a tridimensional movement analysis system was used. Modifications in gait and prehension were identified when they were combined, especially for the most difficult prehension conditions. The grasping task caused an adaptation in gait since participants preferred to adopt a more conservative strategy, increasing their dynamic stability during the approach phase and when grasping the dowel. Based on these results, it is possible to suggest that prehension was superimposed on gait, although the adaptations in motor behavior were global, since both motor patterns (i.e., walking and prehension) were changed to perform the task successfully with different levels of difficulty. It is possible to suggest that motor performance of fallers in the combined task of walking and grasping is more impaired than in no-fallers (for instance, decreased step velocity, increased step duration, decreased wrist velocity and peak grip aperture velocity). Moreover, older adults with history of falls presented a greater reduction in COM AP velocity when compared to older adults without history of falls. The combined task paradigm used in the present study showed some changes in motor control strategy of fallers older adults when performing walking and prehension combined. In addition, motor patterns (walking and grasping) of older adults (fallers and no-fallers) were modified in function of the level of manual task difficulty. The analysis of the relative motion allowed the quantification of the changes in the coordination pattern of the combined task involving walking and prehension for flexion/extension and abduction/adduction movements. For flexion/extension movements, a more in-phase and a less anti-phase pattern was identified in the grasping condition compared to walking through when right shoulder was analyzed relative to left shoulder and right hip. For adduction/abduction movements, when right shoulder was analyzed relative to left shoulder and right hip, it was observed less in phase pattern. In addition, we found a less anti-phase pattern for right shoulder-left shoulder and right shoulder-left hip couplings. However, the changes in motor coordination were not affected by the manual task difficulty for young adults and older adults with and without history of falls. This result suggests that changes in coordination are more general while specific changes in upper limb movement are necessary to deal with different task demands. Finally, older adults with history of falls presented a different pattern of coordination than young adults, such as, a more anti-phase pattern for right shoulder-right hip coupling and a less anti-phase pattern for right shoulder-left hip coupling during the combined task. Thus, it seems that older adults with history of falls decouple the walking and prehension tasks, differently of young adults and older adults without history of falls.