This thesis examines the effects of secondary tasks and click trains upon temporal judgement in the context of a Pacemaker-Gate-Counter (PGC) model. All the timing experiments reported employ a paradigm in which subjects are first trained to reliably reproduce a 2.5 s target interval, and are then required to perform time production with a concurrent secondary task. Previous research with digit memory loads has shown that varying memory load had no impact upon concurrent time production (Fortin & Breton, 1995; Fortin & Masse, 1999). Here, it is shown that increasing pitch memory load lengthens time production, but that this is not the case for a colour memory task, or a timbre memory task. The effect obtained with pitch is replicated, and it is demonstrated that the effect is directly due to the processing requirements of retaining pitch information. Furthermore, the pitch effect is not due to a difference in attentional requirements between retaining pitch and retaining digits. Finally, it is shown that the lengthening of time production also occurs when a concurrent duration memory load is increased. In confirmation of previous research (e.g. Fortin, Rousseau, Bourque, & Kirouac 1993), it is shown that when memory-search is performed concurrently with time production, increasing the number of items to be searched causes a lengthening of time production. A novel finding is that the increase in mean time produced is not accompanied by an increase in standard deviation. Furthermore, it is shown that the shortening of mean time production caused by concurrent click trains does not interact with the increase caused by concurrent memory search, and is accompanied by a reduction in standard deviation. These findings are taken to support the separation made in the PGC model between the Pacemaker and Gate components. Overall, the data presented in this thesis provide a number of constraints upon future theorising within the framework of the PGC model and other similar models.

Sensory motor deficits, although not part of the diagnostic criteria, are frequently reported in autism spectrum disorder (ASD). The ob jective of this project is to study the temporal and spatial dynamics of an approximately periodic motor activity (circle drawing) in children with ASD. The natural rhythm of periodic motor activities such as circle drawing are known to exhibit statistical persistence in typically developing individuals. A sample of 15 children aged 4 to 8 years, with a primary diagnosis of ASD were asked to draw circles using a computerized tablet and pen, which record spatio-temporal data. Results were compared with those of 19 typically developing children. While no differences were seen in statistical persistence, differences were observed in timing of discontinuous circle drawing and in kinetic process variable such as grip and axial forces. Understanding the specific nature of graphomotor deficits is the first step towards developing targeted treatment for these impairments.

Sensory motor deficits, although not part of the diagnostic criteria, are frequently reported in autism spectrum disorder (ASD). The ob jective of this project is to study the temporal and spatial dynamics of an approximately periodic motor activity (circle drawing) in children with ASD. The natural rhythm of periodic motor activities such as circle drawing are known to exhibit statistical persistence in typically developing individuals. A sample of 15 children aged 4 to 8 years, with a primary diagnosis of ASD were asked to draw circles using a computerized tablet and pen, which record spatio-temporal data. Results were compared with those of 19 typically developing children. While no differences were seen in statistical persistence, differences were observed in timing of discontinuous circle drawing and in kinetic process variable such as grip and axial forces. Understanding the specific nature of graphomotor deficits is the first step towards developing targeted treatment for these impairments.

Timing can be defined as the ability to perceive temporal sequences and regulate timed behaviors. As in other animals, our ability to make accurate time estimations is crucial in order to accomplish several activities. Organisms can process time over a wide range of durations ranging from microseconds to days. In the middle of these extremes is the hundreds of milliseconds to seconds range which is important for many everyday behaviors, such as walking, speaking and dancing. Yet, how this is managed remains poorly understood. Some central issues with regard time processing in this particular time range are whether timing is governed by one, or by several different mechanisms, possibly invoked by different effectors used to perform the timing task, as well as, if cognitive capacities are also involved in rhythmic motor timing. This thesis includes three studies. Study I investigated the effects of short- term practice on a motor timing task. Analyses of the timing variability indicated that a substantial amount of learning occurred in the first hour of practice and declined afterwards, exhibiting no trend for further decrease across the remaining 60 or 210 minutes. This effect was similar across effector, amount of feedback, and interval duration. Our results suggested that training effects influenced mainly motor precision and raised the question of whether motor timing training influenced also cognitive capacities. Study II investigated the relationship between motor timing and cognition. Specifically, participants had to train a sensorimotor synchronization task (SMS) over several days, and the question was whether this training would improve cognitive performance. A near transfer effect was found between the sensorimotor synchronization task and the sustained attention task, indicating that sustained attention is involved in motor timing. Study III compared the timing variability between the eyes and the hands, as a function of four different intervals, in order to examine whether these systems are temporally controlled by the same or different mechanism(s). The results showed several positive correlations in variability, between the eye and the finger movements, which, however, were significant only for the longer intervals. In addition, they were differences in variability between the eye and the hand, for the different interval durations. In general, the pattern of results from these studies suggested that voluntary motor timing is managed by overlapping distributed mechanisms and that these mechanisms are related to systems that manage cognitive processes, such as attention. The results partially explain the well-known relationships between cognitive ability and timing.

No description available.

<p>Many daily motor tasks involve the precise control of both force level and motor timing. The neural mechanisms concurrently managing these movement parameters remain unclear, as the dominant focus of previous literature has been to examine each in isolation. As a result, little is understood regarding the contribution of various sensory modalities to force output and interval production in sequential motor tasks. This thesis uses a sequential force production task to investigate the roles of visual and somatosensory feedback in the timed control of force. In Chapter 2 we find that removal of visual force feedback resulted in specific force output errors, but leaves motor timing behavior relatively unaffected according to predictions of the two-level timing model by Wing and Kristofferson (1973). In Chapter 3, we show that force output errors exhibited in the absence of a visual reference may be related to the processing of reafferent somatosensation from self-generated force pulses. The results of Chapter 4 reveal evidence that force errors exhibited following visual feedback removal are consistent with a shift in the perceived magnitude of force output and that the direction of error may be determined by prior task constraints. In Chapter 5 we find evidence of effector-specificity in the processing of and compensation for reafferent somatosensation. Lastly, in Chapter 6 we find that the interplay between audition and somatosensation in the control of sound level by the vocal effectors resembles that which is observed between vision and somatosensation in the control of force by the distal effectors.</p> / Doctor of Philosophy (PhD)

Recent investigations suggest that rhythmic movements rely on two distinct timing systems: event and emergent timing. Event timing is based on an explicit internal representation of the temporal interval marked by clear perceptual detectible events whereas emergent timing is derived from the dynamics of smooth and continuous movements. However, crucial aspects of the distinction between these mechanisms remain unclear. This thesis investigates the role of expectancy and skill in the internal representation of time in event timing and emergent timing. Chapter 1 introduces the theoretical framework that supports the differentiation between event and emergent timing mechanisms and presents the hypotheses that were tested. Chapter 2 describes a series of five experiments that investigated the role of expectancy through examining the effect of a single unexpected perturbation of feedback content (e.g. pitch, timbre, intensity) on timing of finger tapping. Chapter 3 expands this question by investigating the effect of unexpected auditory perturbations on two types of timed movements: event and emergent timing. The role of expertise and training on motor timing is the subject of discussion of Chapters 4 to 6 where a total of 4 experiments tested the effect of expertise and music training on accuracy of finger tapping and circle drawing tasks. More specifically, Chapter 4 compares accuracy levels of experts in movement-based activities (music and sports) with non experts, whereas Chapters 5 and 6 focus on the effect of music training on event and emergent timing in students of 10 to 14 years of age. Finally, Chapter 7 reviews and discusses the main findings of this body of work with respect to current theories of timing and movement. Foremost, these data challenge current models of human movements controlled by event and emergent timing mechanisms demonstrating that expectancy and training are crucial in determining the timing strategy and the type of expectancy mechanisms adopted to perform distinct rhythmic movements / Estudos recentes sugerem que movimentos rítmicos dependem de dois sistemas distintos para controle do tempo, chamados tempo emergente e discreto. Sugere-se que tempo discreto baseia-se em uma representação interna do tempo intervalar que é marcada por eventos perceptuais evidentes, enquanto tempo emergente origina-se da própria dinâmica dos movimentos contínuous. No entanto, aspectos cruciais da diferença entre esses mecanismos ainda necessitam ser examinados. Esta tese investiga o papel de expectativas e treino no controle temporal de movimentos rítmicos contínuous e discretos. Capítulo 1 introduz as bases teóricas que subsidiam as hipóteses testadas no presente trabalho. Capítulo 2 descreve uma série de cinco experimentos que investigam a importância da retroalimentação auditiva e dos mecanismos de expectativa, e assim examina o efeito de uma perturbação inesperada e transitória no conteúdo do feedback (e.x. altura, timbre, intensidade) na precisão temporal de movimentos rítmicos discretos (i.e. finger tapping). Capítulo 3 expande essa investigação e analisa o efeito de perturbações inesperadas da retroalimentação auditivo em tarefas de movimentos contínuos, como desenhar círculos repetidamente. O papel do treinamento para o controle temporal é foco de discussão nos Capítulos 4 a 6, onde se descrevem um total de quatro experimentos que testam o efeito de expertise e treino na precisão de movimentos em tarefas de finger tapping e desenho de círculos. Mais especificamente, Capítulo 4 compara a performance de músicos e atletas com participantes sem nenhum treinamento nestas áreas a fim de examinar o papel do treinamento no controle motor, enquanto os Capítulo 5 e 6 focam no efeito do treino em música no controle temporal de movimentos rítmicos discretos e contínuous em estudantes de 10 a 14 anos de idade. Capítulo 7 revisa e conclui as discussões propostas com base nos principais resultados descritos neste trabalho. Em suma, os resultados apresentam novas e relevantes informações a respeito da importância de expectativas e do treinamento no controle temporal de movimentos rítmicos, cujas implicações podem contribuir significativamente para áreas relacionadas à pedagogia e reabilitação motora. Além disso, esta tese apresenta novas informações que ampliam modelos atuais sobre os mecanismos envolvidos no controle temporal de movimentos rítmicos demonstrando a importância do papel de expectativas, retroalimentação auditiva e do treinamento para determinar os diferentes mecanismos de expectativa adotados pelo sistema nervoso na execução de movimentos rítmicos

Background Although trainers and athletes consider ‘good timing skills’ to be critical for optimal sport performance, little is known in regard to how sport-specific skills may benefit from timing training. Thus, assuming that all motor performances are mediated by an internal timing mechanism, enhanced motor timing is expected to have positive effects on both planning and execution of movement performance, and consequently on complex sports actions as golf or soccer. Accordingly, in order to increase our knowledge of the importance of motor timing and possible effects of timing training, this thesis examines the effects of synchronized metronome training (SMT), thought to improve the execution of motor programs and to enhance motor skills in golf and soccer players. Methods Study I examined the effects of SMT on motor timing abilities and its potential effect on golf shot accuracy and consistency in 25 experienced male golfers. Additionally, Study II examined the effects of SMT on the spatiotemporal movement organisation and dynamics of the golf swing performance, as captured by kinematic measurements and analyses in thirteen male golfers. Study III examined the effect of SMT on accuracy and variability in a soccer specific, cross-pass task in elite and sub-elite female soccer players. Moreover, the underlying brain activity was assessed by means of functional magnetic resonance imaging (fMRI) to investigate the corresponding neural activity when passively observing the cross-pass task, and the possible pre- to post training effects. Results SMT was shown to improve motor timing ability, by means of less timing asynchrony and with associated changes in timing variability, in both golf- and soccer-players. Additionally, significant improvements in golf shot and soccer cross-pass performance, by means of significant increase in outcome accuracy combined with a decrease in outcome variability was found. From the kinematic investigation in Study II, results indicate that improved motor timing, as an effect of SMT, lead to a more coordinated and dynamic swing performance, and with decreased variability in the temporal structure of the swing motion. Finally, it was found that SMT induces changes in the activity of the action observation network (AON), underpinning action observation and action prediction, by means of decreased activation within bilateral cerebellum, fusiform gyrus and superior temporal gyrus. These findings hint at a more efficient pattern of neural recruitment during action observation, after SMT. Conclusion In summary, this thesis provides evidence that four weeks of SMT improved the participant’s motor timing and synchronization abilities, and showed influence on both behavioral and neurophysiological motor programs and skill performance in golf and soccer players. Thus, by improved outcome accuracy and decreased variability, affecting the coordinated movement pattern and organisation, as well as affecting the associated underlying brain activation.

Recent investigations suggest that rhythmic movements rely on two distinct timing systems: event and emergent timing. Event timing is based on an explicit internal representation of the temporal interval marked by clear perceptual detectible events whereas emergent timing is derived from the dynamics of smooth and continuous movements. However, crucial aspects of the distinction between these mechanisms remain unclear. This thesis investigates the role of expectancy and skill in the internal representation of time in event timing and emergent timing. Chapter 1 introduces the theoretical framework that supports the differentiation between event and emergent timing mechanisms and presents the hypotheses that were tested. Chapter 2 describes a series of five experiments that investigated the role of expectancy through examining the effect of a single unexpected perturbation of feedback content (e.g. pitch, timbre, intensity) on timing of finger tapping. Chapter 3 expands this question by investigating the effect of unexpected auditory perturbations on two types of timed movements: event and emergent timing. The role of expertise and training on motor timing is the subject of discussion of Chapters 4 to 6 where a total of 4 experiments tested the effect of expertise and music training on accuracy of finger tapping and circle drawing tasks. More specifically, Chapter 4 compares accuracy levels of experts in movement-based activities (music and sports) with non experts, whereas Chapters 5 and 6 focus on the effect of music training on event and emergent timing in students of 10 to 14 years of age. Finally, Chapter 7 reviews and discusses the main findings of this body of work with respect to current theories of timing and movement. Foremost, these data challenge current models of human movements controlled by event and emergent timing mechanisms demonstrating that expectancy and training are crucial in determining the timing strategy and the type of expectancy mechanisms adopted to perform distinct rhythmic movements / Estudos recentes sugerem que movimentos rítmicos dependem de dois sistemas distintos para controle do tempo, chamados tempo emergente e discreto. Sugere-se que tempo discreto baseia-se em uma representação interna do tempo intervalar que é marcada por eventos perceptuais evidentes, enquanto tempo emergente origina-se da própria dinâmica dos movimentos contínuous. No entanto, aspectos cruciais da diferença entre esses mecanismos ainda necessitam ser examinados. Esta tese investiga o papel de expectativas e treino no controle temporal de movimentos rítmicos contínuous e discretos. Capítulo 1 introduz as bases teóricas que subsidiam as hipóteses testadas no presente trabalho. Capítulo 2 descreve uma série de cinco experimentos que investigam a importância da retroalimentação auditiva e dos mecanismos de expectativa, e assim examina o efeito de uma perturbação inesperada e transitória no conteúdo do feedback (e.x. altura, timbre, intensidade) na precisão temporal de movimentos rítmicos discretos (i.e. finger tapping). Capítulo 3 expande essa investigação e analisa o efeito de perturbações inesperadas da retroalimentação auditivo em tarefas de movimentos contínuos, como desenhar círculos repetidamente. O papel do treinamento para o controle temporal é foco de discussão nos Capítulos 4 a 6, onde se descrevem um total de quatro experimentos que testam o efeito de expertise e treino na precisão de movimentos em tarefas de finger tapping e desenho de círculos. Mais especificamente, Capítulo 4 compara a performance de músicos e atletas com participantes sem nenhum treinamento nestas áreas a fim de examinar o papel do treinamento no controle motor, enquanto os Capítulo 5 e 6 focam no efeito do treino em música no controle temporal de movimentos rítmicos discretos e contínuous em estudantes de 10 a 14 anos de idade. Capítulo 7 revisa e conclui as discussões propostas com base nos principais resultados descritos neste trabalho. Em suma, os resultados apresentam novas e relevantes informações a respeito da importância de expectativas e do treinamento no controle temporal de movimentos rítmicos, cujas implicações podem contribuir significativamente para áreas relacionadas à pedagogia e reabilitação motora. Além disso, esta tese apresenta novas informações que ampliam modelos atuais sobre os mecanismos envolvidos no controle temporal de movimentos rítmicos demonstrando a importância do papel de expectativas, retroalimentação auditiva e do treinamento para determinar os diferentes mecanismos de expectativa adotados pelo sistema nervoso na execução de movimentos rítmicos

Good timing is important for all daily motion, even more so for athletes where the smallest movements can make the difference between a goal and miss. Despite this, there has been little research into just how timing ability is related to sport performance. Therefore the present study used a between-within groups experimental design with a sample of female elite- and semi-elite soccer players to describe the effects of a synchronised metronome training (SMT) intervention on lower-limb movement, and accuracy and speed, in a soccer-related stepping task. Participants were randomly assigned to receive SMT (n = 12) or to the control group (n = 12). The SMT group received 12 hours of Interactive Metronome (IM) training over four weeks. Pre- and post-test results showed a strong effect of SMT in improving timing and rhythmic ability. An effect of SMT on accuracy in the stepping task was seen, signifying an effect on motor planning ability. Correlational analyses showed some evident effects of IM on the kinematic parameters, as indicated by relationship between timing and rhythmicity ability with increased movement segmentation, though this did not reach significance. These results present new information and provides support for kinematic analysis to be used in future studies to address the effect of SMT. / God timing är viktig för alla dagliga rörelser, och än mer viktigt är det för idrottare där minsta lilla rörelse kan innebära skillnaden mellan mål och miss. Trots detta finns lite forskning om hur förmåga till timing kan förbättra sportsliga prestationer. Huvudsyftet med denna studie var att undersöka hur synkroniserad metronomträning (SMT) påverkade prestationen och rörelsedynamik i en fotbollsrelaterad uppgift. I studien deltog 24 aktiva fotbollsspelare från Damallsvenskan och Division 1, varav 12 fick träna med SMT under fyra veckor. Resultatet visade att SMT påverkade exaktheten i utförandet av den fotbollsrelaterade uppgiften, vilket indikera en effekt på motorplaneringsförmåga. Denna studie jämför för första gången 3D-kinematikdata från före- och efter träning med SMT samt med en kontrollgrupp, 3D-kinematikanalysen av rörelsesegmentering och kumulativ 3D-distans visade inga övertygande relationer mellan SMT och rörelsedynamiken efter IM-träning. Däremot visade korrelationen stöd för en relation mellan rörelsesegmentering och timingförmåga. Därför stödjer denna studie tidigare forskning kring timing och motorisk prestation, och det finns tillräckligt med bevis för att motivera vidare analyser av kinematiska parametrar för att studera effekten av SMT och rörelsedynamik.