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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.
91

Aspects of Voluntary Control of Heart Rate and Electroencephalographic Alpha through Biofeedback

Scott, William B. January 1979 (has links)
Note:
92

Evaluation of biofeedback components for the management of acute stress in healthcare

Kennedy-Metz, Lauren Rose 27 November 2018 (has links)
Medical error is the third leading cause of death in the United States, with surgery being a critical area for improvement. Of particular interest for this dissertation is understanding and mitigating the impact of acute stress experienced by surgeons. Previous research demonstrates the detrimental effects mismanaged acute stress can have on cognitive performance integral in optimal surgical practice. Biofeedback consists of objectively monitoring signs of stress, presenting physicians with their own physiological output in real time. Introducing appropriate, targeted coping mechanisms when they are most needed may facilitate behavioral adjustments in the face of acute stress. The goal of this dissertation research was to evaluate the potential benefit of biofeedback and coping instructions, measured by reduced perceived and physiological stress, and improved task performance. In the first study, college students participated in a first-person shooter videogame while receiving visual coping instructions. Instructions that were presented at moments of elevated stress improved downstream physiology compared to randomly administered instruction, and the presence of coping instructions was more beneficial than their absence at highly stressful times. In the second study, I adapted and validated a computer-based task to focus on components of workload experienced by physicians. This study yielded one high-stress and one-low stress version of a more demographic-appropriate task. In the final study, medical students and residents completed this task. The independent variables tested included a visual biofeedback interface, intermittent auditory coping instructions, and/or brief training on stress management and emotional intelligence. Results from this study showed that despite high cognitive workload experienced by participants receiving both biofeedback and coping instructions, performance across stress levels was indistinguishable, and physiological indicators of stress immediately following discrete coping instructions was reflective of decreased stress. Taken together, the results of these studies validate the generation of a new lab-based task to induce stress among healthcare providers, and the physiological and performance benefits associated with physiologically-based coping instructions. Future work should investigate how these concepts can be tailored towards surgical workflow with feedback modality in mind, extended to teams, and/or scaled up to higher levels of fidelity to better capture the work environment. / Ph. D. / Medical error is the third leading causing of death in the United States, with surgery being a critical area for improvement. Many medical errors are preventable, and previous research has shown that inappropriately managed acute stress is responsible for many errors. Biofeedback is one way to externalize stress states, enabling individuals to monitor their own stress, even as it is changing. With rapid advancement in technological functionality, sensors hold promise not only for personal body data, but also active interventions such as biofeedback. Biofeedback is the process of actively monitoring physiology on an external device, and updating behaviors based on that physiology. Its role as a stress management tool is growing. Commercially available sensor devices are widespread, and are generating and archiving thousands of data points every day. Rather than simply archiving this data, we can use sensor technology to inform us of our current physiological and cognitive states in real time, and use that information to alter our response to stressful stimuli to achieve more favorable outcomes. This concept can be applied specifically to address how to cope when experiencing high levels of stress. For individuals working in high-stakes environments on a daily basis, such as surgeons, using physiological data to manage stress could have the added benefit of improving performance that might otherwise suffer due to mismanaged stress. The goal of this dissertation research is to explore the potential benefit of using biofeedback and specific coping strategies to reduce stress and improve performance among healthcare providers. This research consisted of different studies, all using experimental psychology approaches and all geared towards evaluating different conditions of either visual coping instructions, training on emotional intelligence concepts as they relate to coping under stress, visual biofeedback, and/or auditory coping instructions. The results of these studies validate the generation of a new lab-based task to induce stress among healthcare providers, support the benefit of introducing coping instructions in response to elevated physiological signs of stress, and support the need for future assessments.
93

The Reduction of Tension Headache Using EMG Biofeedback and Locus of Control as Predictors

Grier, Finlay 08 1900 (has links)
This study investigates the status of biofeedback treatment and locus of control (LOC) affiliation on the reduction of tension headache. Three LOC groups designated as internals, powerful-other externals and chance externals (using Wallston and Wallston's, 1978, Multidimensional Health Locus of Control Scale) were administered an eight week electromyogram (EMG) frontalis muscle biofeedback training program using an Autogen 1700 biofeedback unit. Subjects were 12 female and four male undergraduate students who had a history of tension headache. Results indicated no significant difference in frontalis muscle tension between the beginning and end of sessions in either a biofeedback or self-control condition for any of the LOC groups. Further, there was no significant difference among LOC groups in ability to reduce muscle tension in either the training or self-control condition. Finally, neither biofeedback training nor LOC groups were significant predictors of headache reduction. Extreme within-group variability and small sample size affected study findings and these and other implications for future research are discussed.
94

Attainment of Low Levels of Muscle Tension: Biofeedback-Assisted/Cue-Controlled Relaxation and Biofeedback Training Compared

Ewing, Jack Winston 08 1900 (has links)
Cue-controlled relaxation appeas to have several advantages over prominent anxiety-reduction treatments. It does not require the formulation of conditioned stimulus hierarchies nor the use of mental imagery as does systematic desensitization nor the application of noxious stimularion (farradic shock) utilized in anxiety relief. However, its efficacy, in quantitative terms, has not been determined. The present study compared the effectiveness in attainment of relaxation of instructional set, biofeedback training, and biofeedback-assisted/cue-controlled relaxation training procedures. Results indicate that cue-controlled relaxation training was more effective in terms of mean level of frontal is EMG and degree of maintenance of low EMG levels than either biofeedback training or instructions.
95

EMG Biofeedback Training: Effect on Behavior of Children with Activity-Level Problems

Henry, David L. 05 1900 (has links)
The relationships between muscle-tension level, motoric-activity level, and academic performance in the laboratory setting are investigated. Three participants were reinforced for reducing and increasing their tension levels, alternately, while engaged in a simulated academic task, and the effects of each on the rate of activity and academic performance were measured. Measures were also obtained on the rate of activity and occurrence of problem behavior in the subject's homes. Significant treatment differences were found which support a direct relationship between tension and activity level so that a decrease in EMG level was associated with a decrease in motoric activity, and an increase in EMG level was associated with an increase in motoric activity. The efficacy of using EMG biofeedback to train relaxation in children with activity-level problems to control their symptoms is supported, especially where such a technique can be used in a specific task-oriented situation.
96

Biofeedback and Control of Skin Cell Proliferation in Psoriasis

Benoit, Larry J. 12 1900 (has links)
The present study was designed to determine the effect of skin-temperature-biofeedback training on cellular proliferation in three psoriasis patients. It was hypothesized that (a) psoriasis patients would be able to consciously decrease skin temperature of psoriatic tissue, and (b) there would be a positive correlation between rate of cellular proliferation and temperature change. Results obtained indicated biofeedback training to be effective in decreasing the surface temperature of psoriatic tissue. A 2 X 7 analysis of variance for two repeated measures indicated the change in skin temperatures as a function of sample period to be significant, F (6,26) = 3.29, p < .02. Generalization of temperature-training effects from the biofeedback to the no-feedback condition were observed. Rate of proliferation decreased from pretraining to posttraining biopsies.
97

Efeito da reabilitação precoce do assoalho pélvico com biofeedback sobre a função erétil de pacientes submetidos à prostatectomia radical: estudo prospectivo, controlado e randomizado / Effect of early posteoperative pelvic-floor biofeedback on erectile function in men undergoing radical prostatectomy: a prospective, randomized, controlled trial

Prota, Cristina 25 November 2010 (has links)
INTRODUÇÃO: Disfunção erétil (DE) e incontinência urinária são complicações comuns em pacientes submetidos à prostatectomia radical (PR). Sabe-se que a reabilitação do assoalho pélvico com biofeedback pode antecipar o retorno da continência urinária; porém, os efeitos sobre a função erétil não são conhecidos. Neste trabalho estudou-se o efeito da reabilitação precoce do assoalho pélvico com biofeedback sobre a função erétil, após 12 meses da PR. MÉTODOS: Realizou-se um estudo prospectivo, controlado e randomizado. Foram convidados a participar do estudo 56 pacientes sem disfunção erétil que escolheram a PR para tratamento do câncer de próstata localizado, e que poderiam cumprir a agenda de seguimento ambulatorial. A função erétil foi avaliada pelo índice internacional de função erétil (IIEF5). Foram considerados potentes os pacientes com escore IIEF 5 >= 20. Os pacientes foram randomizados para um grupo de tratamento (n=26), recebendo reabilitação do assoalho pélvico com biofeedback uma vez por semana e orientação para exercícios domiciliares ou para um grupo controle (n=26), no qual os pacientes receberam as instruções habituais do urologista. Durante o estudo, nenhum paciente recebeu tratamento com medicamentos para DE. Foram considerados continentes os pacientes que usavam no máximo um absorvente por dia. A associação entre recuperação da continência e recuperação da potência foi avaliada. RESULTADOS: Nove pacientes do grupo de tratamento e dez do grupo controle foram precocemente excluídos do estudo, antes da avaliação inicial do primeiro mês. As causas de exclusão foram: por abandono do programa (8 pacientes), complicações pós-operatórias (9), necessidade de radioterapia adjuvante (2). Não houve diferença entre os grupos em relação à idade, índice de massa corpórea, presença de diabetes, bem como quanto à função erétil pré-operatória. Nos dois grupos observou-se significativa redução da função erétil. Após 12 meses da cirurgia 8 (47,1%) pacientes do grupo de tratamento recuperaram ereção, contra 2 (12,5%) pacientes no grupo controle (p=0,032). A redução do risco absoluto foi de 34,6% (3.8-64%)IC95%. O número necessário para tratar foi de 3 (1.5-17.2; IC95%). Foi observada forte associação entre recuperação da potência e da continência, de tal forma que a probabilidade de estar potente nos pacientes continentes foi 2,6 vezes maior do que nos pacientes incontinentes (p=0,017; [1,45-4,69] IC 95%). CONCLUSÃO: A reabilitação precoce do assoalho pélvico com biofeedback parece ajudar na recuperação da função erétil após a PR. A continência urinária foi um bom indicador da recuperação da função erétil, conferindo uma chance maior de sua recuperação. / INTRODUCTION: Erectile dysfunction (ED) and urinary incontinence are common complications in the early postoperative follow-up of patients undergoing radical prostatectomy (RP). Previous studies indicate that the preservation of potency is not associated with the recovery of urinary continence after RP. Although pelvic-floor biofeedback training (PFBT) may improve urinary continence following RP, its effects on the recovery of potency are unknown. METHODS: Fifty-two patients who elected PR for treatment of clinically localized prostate cancer and who could comply with the ambulatory treatment schedule were invited to participate in this prospective study. Patients were randomized for a treatment group (n=26) receiving PFBT once a week for 3 months and home exercises or a control group (n=26), in which patients received the usual instructions to contract the pelvic floor. Patients were not allowed to receive drug treatment for ED throughout the study duration. Erectile function was evaluated with the International Index of Erectile Function-5 (IIEF-5) before surgery and one, three, six and 12 months postoperatively. Patients were considered potent when they had a total IIEF-5 score of >= 20. Additionally, the continence status was assessed and patients were considered continent when the use of pads was <= 1/day. The association of continence and recovery of potency was evaluated. RESULTS: Nine patients in the treatment group and 10 in the control group were excluded due to failure to return for the evaluation (8 pts), postoperative complications (9 pts), need for adjuvant radiotherapy (2 pts). Preoperative assessment did not show differences in age, body mass index, and diabetes between the groups. There was a significant reduction in IIEF 5 scores after surgery in both groups. In the treatment group 8 (47.1%) patients recovered potency 12 months postoperatively, as opposed to 2 (12.5%) in the control group (p=0.032). The absolute risk reduction was 34.6% (95% CI: 3.8-64%). The number needed to treat was 3 (95% CI: 1.5-17.2). A strong association between recovery of potency and urinary continence was observed, with continent patients having a 2.6 higher chance of being potent than incontinent patients (p=0.017; 95% CI: 1.45-4.69). CONCLUSIONS: Early PFBT appears to have a significant impact on the recovery of erectile function after PR. Urinary continence status was a good indicator of erectile function recovery, with continent patients having higher chance of being potent than incontinent patients.
98

Avaliação dos efeitos do treinamento em neurofeedback sobre o desempenho cognitivo de adultos universitários / Evaluation of neurofeedback training on cognitive performance of college students

Appolinario, Fabio 17 December 2001 (has links)
O neurofeedback é um processo psicofisiológico de aprendizagem por meio do qual o indivíduo obtém controle sobre a freqüência de suas ondas cerebrais. Este estudo objetivou avaliar o efeito do treinamento do ritmo beta inferior (12-15Hz) sobre o córtex sensoriomotor e a concomitante inibição do ritmo teta (4-8Hz) na mesma área, sobre o desempenho atencional, mnemônico e cognitivo de adultos normais de nível universitário. Formou-se um grupo experimental e um grupo controle com 11 sujeitos cada, com idade média de 25,7 anos, estudantes de uma instituição de ensino superior particular em São Paulo. Todos os sujeitos foram submetidos a pré e pós-testes de inteligência não-verbal (Matrizes Progressivas de Raven Escala Avançada), verbal (V-47), atenção (D2) e memória (Fator M Bateria Cepa). O experimento, que durou dois meses, submeteu os sujeitos experimentais a 36 sessões (em média) de treinamento em neurofeedback, com a duração de 15 minutos cada e freqüência de três vezes por semana. Os resultados indicaram uma melhora significante nos processos atencionais, mnemônicos (icônicos) e edutivos (inteligência não-verbal). Não foram obtidas melhoras significantes nos processos mnemônicos (ecóicos) e reprodutivos (inteligência verbal). A comparação do grupo experimental com o grupo controle indicou a não relevância do efeito aprendizagem (teste-reteste) nas tarefas utilizadas para a avaliação dos sujeitos / Neurofeedback is a psychophysiological process where visual stimuli and sounds are employed to reinforce voluntary control over EEG patterns. This study evaluated the effect of low beta (12-15Hz) increase and theta (4-8Hz) inhibit training over sensorimotor cortex on attention, memory and cognitive performance of young adults college students. Experimental and control groups were formed by 11 volunteers subjects each, aging 25,7 years on average. All subjects were submitted to pre and post evaluations of non-verbal (Ravens Advanced Progressive Matrices) and verbal intelligence (V-47 test), attention (D2 test) and memory (Fator M Bateria Cepa). The experiment was conducted along two months, subjects having an average of 36 sessions (15 minutes each), three times a week. Results provide strong evidences of significant improvement on attention, visual memory and non-verbal intelligence (eduction). However, it could not be found evidence of significant improvement on auditory memory or verbal intelligence (reproduction). The experimental and control comparision did not indicate test-retest effects on the experiment
99

Impact sur l'expérience utilisateur en environnement virtuel immersif de l'utilisation d'objets connectés portés pour la rétroaction physiologique / Impact on user experience in immersive virtual environment of the usage of smart wearables for biofeedback

Houzangbe, Samory 12 March 2019 (has links)
Les objets connectés ont aujourd’hui pénétré les foyers et, poussés par une société tournée de plus en plus vers le bien-être, ces capteurs mesurent et proposent dorénavant une grande variété de données physiologiques. L’arrivée à maturité des technologies de la réalité virtuelle, couplée avec l’avènement des objets connectés, permet et favorise dès lors de nouvelles perspectives dans la proposition d’expériences immersives enrichies. De nombreux travaux dans le domaine de la réalité virtuelle rapportent l’exploitation des signaux physiologiques. Ceux-ci se basent principalement sur du matériel médical, qui possède des contraintes d’utilisation forte, reste souvent encombrant et limite de fait la mobilité des utilisateurs. Pour tenter de pallier ces limites, nos travaux se concentrent donc sur l’utilisation originale des wearables (objets connectés portés) comme substituts aux capteurs physiologiques traditionnels dans le cadre d’applications immersives. Ce travail de thèse se positionne à mi-chemin entre une étude de faisabilité technologique et une étude fondamentale sur l’expérience utilisateur (UX).Dans ce contexte, l’objectif de nos recherches est de contribuer à la connaissance concernant l’impact de l’utilisation des données physiologiques dans des environnements virtuels immersifs. Nous étudierons en particulier l’influence d’un biofeedback cardiaque, via des capteurs connectés grand public, sur l’engagement utilisateur et le sentiment d’agentivité. Nous avons ainsi mené deux expérimentations nous permettant d’étudier l’impact des différentes modalités de biofeedback sur l’expérience utilisateur. Notre première expérimentation met en place un biofeedback cardiaque dans un jeu d’horreur en réalité virtuelle, permettant d’augmenter le sentiment de peur. Les résultats de cette expérimentationconfortent l’intérêt de l’utilisation de capteurs connectés comme moyen de captation physiologique dans des expériences de réalité virtuelle immersive. Ils mettent également en avant l’impact positif de ce biofeedback sur la dimension d’engagement de l’expérience utilisateur. La deuxième expérience porte sur l’utilisation de l’activité cardiaque comme une mécanique d’interaction obligatoire. Elle est découpée en deux parties, la première permettant de quantifier le niveau de compétence des participants dans le contrôle de leur activité cardiaque et la seconde les plongeant dans une suite de tâches en réalité virtuelle ; le contrôle cardiaque est de fait nécessaire pour les réussir. Les résultats de cette expérience démontrent la possibilité d’utiliser la dite mécanique pour des expériences virtuelles immersives et indiquent un impact positif sur le sentiment d’agentivité, lié au niveau de compétence des participants. Sur un plan théorique, cette thèse propose une synthèse des modèles de l’expérience utilisateur en environnement virtuel et soumet par ailleurs les bases d’un modèle que nous nommons « l’immersion physiologique ». / The internet of things has now entered every home and, with a society more and more focused towards wellness, these sensors measure and offer henceforth a wide variety of physiological data. Virtual reality technologies reaching maturity, coupled with the advent of the internet of things, allow consequently new opportunities to propose improved immersive experiences. If we identify nowadays many virtual reality studies reporting the usage of physiological data, they mainly use medical equipment, which poses strong usability constraints, is often cumbersome and limits mobility. In an attempt to overcome these limitations, this study therefore focuses on the original usage of smart wearables as substitutes for traditional sensors in immersive applications. Thus, this thesis is positioned halfway between a technological feasibility study and a fundamental user experience study.In this context, the objective of our study is to contribute to knowledge about the impact of the use of physiological data in immersive virtual environments. More precisely, the impact of biofeedback, via off-the-shelf smart wearables, on user engagement and the sense of agency. We have thus carried out two experiments allowing us to study the impacts of the different biofeedback modalities on user experience. Our first experiment implements a biofeedback based on heart rate in a virtual reality horror game, allowing to enhance the feeling of fear. The results of this experiment confirm the interest of using smart wearables to capture physiological data for immersive virtual reality experiences. They also highlight the positive impact of this biofeedback on user engagement. The second experiment focuses on the use of cardiac activity as a mandatory interaction mechanism. This experiment is divided into two parts, the first one quantifying the participants’ level of competency in heartrate control and the second one immersing them in a series of tasks in virtual reality ; heartrate control is necessary to complete the different steps of the experience. The results of this experiment demonstrate the possibility of using the said interaction mechanic for virtual reality experiences and indicate a positive impact on the sense of agency, linked with the level of competency of the participants. On a theoretical level, this thesis proposes a synthesis of user experience models in virtual environment and submit the foundations of a model that we call "physiological immersion".
100

A redução do estado de ansiedade dos cobradores de pênalti no futebol / The Reduction of state anxiety in penalty kickers in soccer

Mello, Daniel Donadio de 17 May 2017 (has links)
O futebol é um esporte coletivo, em que desempenhos individuais podem definir o resultado de um jogo ou de um campeonato. Especialmente em cobranças de pênalti, o destino da partida encontra-se nos pés do cobrador. A ansiedade no momento das cobranças de pênalti em jogos de futebol de campo é um dos motivos que podem fazer com que um jogador de futebol não converta a cobrança em gol. Neste estudo experimental controlado foi testado um protocolo de biofeedback e psicologia cognitivo-comportamental com o objetivo de reduzir o estado de ansiedade em atletas de futebol amadores de futebol de campo de 15 e 16 anos de idade. Os participantes do grupo experimental foram avaliados antes de duas competições de pênaltis, que aconteceram antes e depois de quatro encontros de intervenção com o protocolo de biofeedback e psicologia cognitivo-comportamental para a redução de ansiedade dos jogadores de futebol que participaram do grupo ativo, em relação ao grupo controle / Soccer is a collective sport in which individual performances can define the outcome of a game or a championship. Especially at penalties shootouts, the destination of the match is at the feet of the penalty taker. Anxiety at the time of penalty kicks at soccer matches is one of the reasons why a soccer player may not score the goal. In this controlled experimental study, a protocol of biofeedback and cognitive-behavioral psychology was tested with the objective of reducing the state anxiety in 15 and 16 year old amateur soccer athletes. Participants in the experimental group were assessed before two penalty shoot-outs, which took place before and after four intervention sessions with a biofeedback and cognitive-behavioral psychology protocol. The results showed that the protocol was efficient as a method and effective in reducing the anxiety state of soccer players who participated in the experimental group, in comparison to the control group

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