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

Perceptual and Attentional Constraints on 1:1 Bimanual Coordination

Kovacs, Attila J. 2010 May 1900 (has links)
Two experiments were conducted in an attempt to further the understanding of how previously identified intrinsic constraints and perceptual factors interact in influencing the learning and performance of various bimanual coordination patterns. The purpose of Experiment 1 was to determine the influence of Lissajous feedback on 1:1 bimanual coordination patterns (0°, 90°, 180° phase lags) when the movement amplitudes of the two limbs were different. Participants coordinated rhythmic movements of their forearms while being provided separate feedback for each limb (no- Lissajous group) or integrated feedback (Lissajous group). Data from Experiment 1 supports the notion that the lead-lag relationship as well as amplitude assimilation between limbs observed in the literature can be partially attributed to the visualperceptual factors present in the testing environment. When participants are provided integrated feedback in the form of Lissajous plots and templates much of the lead-lag and amplitude assimilation effects were eliminated and relative phase error and variability were also greatly reduced after only 3 min of practice under each condition. Results from recent experiments suggest that when the salient visual information (Lissajous feedback) is removed, performance in bimanual coordination tasks rapidly deteriorates. The purpose of Experiment 2 was to determine if reducing the frequency of feedback presentation will decrease the reliance on the feedback and will facilitate the development of an internal representation that will improve performance when visual feedback is removed. Participants receiving reduced frequency feedback presentation were able to perform a delayed retention test with the feedback removed as well as the test with feedback present. Data from Experiment 2 demonstrates that salient extrinsic Lissajous feedback can effectively be combined with reduced frequency feedback presentation in a way that performance levels, when tested without the availability of feedback, match those obtained when tested in the presence of Lissajous feedback. Taken together the present experiments add to the growing literature that supports the notion that salient perceptual information can override some aspects of the system's intrinsic dynamics typically linked to motor output control. The strong tendencies toward the intrinsic dynamics found in numerous previous bimanual movement studies and the difficulties in producing various coordination patterns may actually represent detrimental effects attributable to the perceptual information available in the environment and the attentional focus participants adopt. Given external integrated salient visual information participants can essentially tune-in and learn difficult bimanual coordination patterns with relatively little practice.
2

The Coordination Dynamics of Multiple Agents

Unknown Date (has links)
A fundamental question in Complexity Science is how numerous dynamic processes coordinate with each other on multiple levels of description to form a complex whole - a multiscale coordinative structure (e.g. a community of interacting people, organs, cells, molecules etc.). This dissertation includes a series of empirical, theoretical and methodological studies of rhythmic coordination between multiple agents to uncover dynamic principles underlying multiscale coordinative structures. First, a new experimental paradigm was developed for studying coordination at multiple levels of description in intermediate-sized (N = 8) ensembles of humans. Based on this paradigm, coordination dynamics in 15 ensembles was examined experimentally, where the diversity of subjects movement frequency was manipulated to induce di erent grouping behavior. Phase coordination between subjects was found to be metastable with inphase and antiphase tendencies. Higher frequency diversity led to segregation between frequency groups, reduced intragroup coordination, and dispersion of dyadic phase relations (i.e. relations at di erent levels of description). Subsequently, a model was developed, successfully capturing these observations. The model reconciles the Kuramoto and the extended Haken-Kelso-Bunz model (for large- and small-scale coordination respectively) by adding the second-order coupling from the latter to the former. The second order coupling is indispensable in capturing experimental observations and connects behavioral complexity (i.e. multistability) of coordinative structures across scales. Both the experimental and theoretical studies revealed multiagent metastable coordination as a powerful mechanism for generating complex spatiotemporal patterns. Coexistence of multiple phase relations gives rise to many topologically distinct metastable patterns with di erent degrees of complexity. Finally, a new data-analytic tool was developed to quantify complex metastable patterns based on their topological features. The recurrence of topological features revealed important structures and transitions in high-dimensional dynamic patterns that eluded its non-topological counterparts. Taken together, the work has paved the way for a deeper understanding of multiscale coordinative structures. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
3

The rhythm that unites: an empirical investigation into synchrony, ritual, and hierarchy

Wood, Connor 21 June 2016 (has links)
Synchrony, or rhythmic bodily unison activities such as drumming or cadence marching, has attracted growing scholarly interest. Among laboratory subjects, synchrony elicits prosocial responses, including altruism and empathy. In light of such findings, researchers in social psychology and the bio-cultural study of religion have suggested that synchrony played a role in humanity’s evolutionary history by engendering collectivistic commitments and social cohesion. These models propose that synchrony enhances cohesion by making people feel united. However, such models overlook the importance of differentiated social relations, such as hierarchies. This dissertation builds on this insight by drawing on neuroscience, coordination dynamics, social psychology, anthropology, and ritual studies to generate a complex model of synchrony, ritual, and social hierarchy, which is then tested in an experimental study. In the hypothesized model, shared motor unison suppresses the brain’s ability to distinguish cognitively between self-caused and exogenous motor acts, resulting in subjective self-other overlap. During synchrony each participant is dynamically entrained to a group mean rhythm; this “immanent authority” prevents any one participant from unilaterally dictating the rhythm, flattening relative hierarchy. As a ritualized behavior, synchrony therefore paradigmatically evokes shared ideals of equality and unity. However, when lab participants were assigned to either a synchrony or asynchrony manipulation and given a collaborative task requiring complex coordination, synchrony predicted a marginally lower degree of collaboration and significantly lower interpersonal satisfaction. These findings imply that unity and equality can undercut group cohesion if the collective agenda is a shared goal that requires interpersonal coordination. My results emphasize that, despite the inevitable tensions associated with social hierarchy, complementary roles and hierarchy are vital for certain aspects of social cohesion. Ritual and convention institute social boundaries that can be adroitly negotiated, even as egalitarian effervescence such as communitas (in the sense of Victor Turner) facilitates social unity and inspires affective commitments. These findings corroborate theories in ritual studies and sociology that caution both against excessive emphasis on inner emotive states (such as empathy) and against excessively rigid conventions or roles. An organic balance between unity and functional differentiation is vital for genuinely robust, long-term social cohesion. / 2018-06-21T00:00:00Z
4

Le processus d’interaction comme attracteur dans la coordination temporelle entre les personnes / The process of interaction as an attractor in the temporal coordination between persons

Laroche, Julien 24 June 2013 (has links)
Les interactions sociales sont souvent vues comme des échanges d’informations au cours desquels des états mentaux individuels se succèdent. Comment pouvons-nous dès lors être « ensemble » et partager un moment ? Dans cette thèse, nous optons pour une perspective centrée sur la coordination temporelle des comportements des personnes en interaction, en nous intéressant aux phénomènes de dynamiques collectives incarnées. Ces dynamiques coordonnent communément les comportements et émergent directement du processus d’interaction mutuel lui-même. Pour évaluer cette proposition, nous avons mené trois expériences. Notre méthodologie générale distinguait trois situations types : une situation de coordination individuelle, une situation pseudo-sociale dans laquelle le comportement doit être coordonné à celui d’une autre personne sans que la réciproque soit vraie, et enfin une situation dans laquelle l’interaction est mutuelle. Une première expérience nous a permis de montrer que la mutualité de l’interaction suffisait à induire une coordination entre les participants, dont les comportements étaient pris dans une dynamique collective qui leur échappait totalement. Ensuite, nous avons montré que la mutualité de l’interaction augmentait la stabilité des interactions rythmiques et provoquait un appariement de la complexité des comportements. Enfin, nous avons montré qu’en dépit d’un environnement commun très structuré, la mutualité de l’interaction induisait une organisation légèrement plus coordonnée du temps. Nous discutons ces résultats en regard de notre objet de recherche et de notre arrière-plan théorique / Social interactions are mostly seen as information exchanges during which individual mental states follow each other. How could we, accordingly, be « toghether » and share a moment ? In this thesis, we took a perspective focused on the temporal coordinations of interpersonal behaviors as they occur in the course of interactions, by studying the phenomenon of embodied collective dynamics. Such dynamics manifest coordinates behaviors mutually and emerge from the interaction process itself. To evaluate this hypothesis, we devised three experimental paradigms. We used a general methodology in which three typical situations are distinguished : the individual situation in which participants possess all the capacities to pursue the goal of the task, a pseudo-social situation in which behavior can be coordinated to the mouvement of an other, and a situation in which the interaction is mutual. In the first experiment, we showed the mutuality of interaction was sufficient to induce participants, whose behaviors were caught in collective dynamics unbeknownst to them. Then, we showed that mutuality of interaction was enhancing the stability of rhythmic interactions as well as the complexity matching between their behaviors. Finally, we showed that, in despite of a temporary structured environment, mutuality of interaction induced a slight more coordinated temporal organization of behaviors. We discuss these results in respect of our object of research and our theoretical background
5

Deception Dynamics: Identifying Patterns of Social Coordination during Truthful and Dishonest Conversation

Malone, MaryLauren January 2017 (has links)
No description available.
6

A Story of Resonance

Raja Galián, Vicente 29 October 2018 (has links)
No description available.
7

The Impact of Coordination Quality on Coordination Dynamics and Team Performance: When Humans Team with Autonomy

January 2017 (has links)
abstract: This increasing role of highly automated and intelligent systems as team members has started a paradigm shift from human-human teaming to Human-Autonomy Teaming (HAT). However, moving from human-human teaming to HAT is challenging. Teamwork requires skills that are often missing in robots and synthetic agents. It is possible that adding a synthetic agent as a team member may lead teams to demonstrate different coordination patterns resulting in differences in team cognition and ultimately team effectiveness. The theory of Interactive Team Cognition (ITC) emphasizes the importance of team interaction behaviors over the collection of individual knowledge. In this dissertation, Nonlinear Dynamical Methods (NDMs) were applied to capture characteristics of overall team coordination and communication behaviors. The findings supported the hypothesis that coordination stability is related to team performance in a nonlinear manner with optimal performance associated with moderate stability coupled with flexibility. Thus, we need to build mechanisms in HATs to demonstrate moderately stable and flexible coordination behavior to achieve team-level goals under routine and novel task conditions. / Dissertation/Thesis / Doctoral Dissertation Engineering 2017
8

Learning to Balance an Inverted Pendulum at the Fingertip: A Window Into the Task and Context-Dependent Control of Unstable Dynamical Objects

Cluff, Tyler 04 1900 (has links)
<p>Our ability to control unstable objects highlights the sophistication of voluntary motor behaviour. In this thesis, we used an inverted pendulum (i.e., stick) balancing paradigm to investigate the task, learning and context-dependent attributes of unstable object control. We hypothesized that learning would mediate the functional integration of posture and upper limb dynamics and expected changes in the task demand and context to be reflected in the control of posture and the upper limb. We found that training increased the average length of balancing trials and applied this result to further investigate the circumstantial properties of unstable object control.</p> <p>We investigated the temporal structure of posture and upper limb dynamics using statistical and nonlinear time series analysis. We demonstrated that subjects used an intermittent strategy to control the inverted pendulum (Chapters 3 and 5) and found that motor learning modulated the statistical and spatiotemporal attributes of posture (Chapter 5) and upper limb displacements (Chapters 2, 3 and 5). We confirmed the balance control strategy was intermittent by showing that posture and upper limb time series are composed of two independent timescale components: a fast component linked to small stochastic displacements and a slow component related to feedback control (Chapters 3, 4 and 5). The interplay between timescale components was affected by the balancing context (Chapter 3) and task demand (Chapter 4).</p> <p>Chapter 5 investigated the acquisition of individual and coupled posture-upper limb control mechanisms. We found that motor learning involved two independent adaptation processes. The first process modified the timescale composition of posture and upper limb displacements and was followed by incremental changes in the occurrence and duration of correlated posture-upper limb trajectories. In Chapter 6, we investigated learning-mediated changes in multijoint coordination and control. Motor learning led to the flexible, error-compensating recruitment of individual joints and we showed that the preferential constraint of destabilizing joint angle variance was the putative mechanism underlying performance.</p> <p>This thesis performed a detailed examination of unstable object control mechanisms. The undertaken studies have provided knowledge about the acquisition and adaptation of control mechanisms at multiple levels of the motor system. Our data provide convergent evidence that the control mechanisms governing complex human balancing tasks are intermittent and modulated by the task and context.</p> / Doctor of Philosophy (PhD)

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