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Effect of reward on visual perceptual decision-making in humans and non-human primatesCicmil, Nela January 2012 (has links)
When primates make decisions about sensory signals, their choices are biased by the costs and benefits associated with different possible outcomes. However, much remains unknown about the neuronal mechanisms by which reward information is integrated into the perceptual decision-making process. I used electrophysiological, psychophysical and imaging techniques to explore the effect of reward on sensory representations, whilst humans and monkeys made perceptual judgements about structure-from-motion (SFM) stimuli. Electrical microstimulation of visual area V5/MT in the macaque monkey was used to bias per- ceptual judgements, under different available reward sizes for correct choices. The behavioural effect of microstimulation interacted with available reward, and, in the context of a drift diffu- sion model of decision-making, the results demonstrated that reward must influence sensory processing before visual signals and micro stimulation signals are accumulated in sensorimotor areas. In a parallel human psychophysics experiment, viewers made decisions about SFM stim- uti whilst their choices were biased towards one outcome or the other by unequal pay-offs. A full drift -diffusion model was fitted to human choice and reaction time data. There was a signif- icant effect of reward on model drift rate, a parameter known to be dependent upon evidence represented in sensory brain regions. A second set of experiments used magneto encephalography (MEG) to explore activity in visual , areas in human cortex and the effects of reward. Brain responses to retinotopic visual stimuli were localized with three different MEG source analysis methods, and localization accuracy was evaluated by comparison with fMRI maps obtained in the same individuals. The results demon- strated that the beamformer and minimum norm estimate (MNE) methods were most suitable for investigating early visual activity with MEG. Human brain activity was then recorded with MEG whilst viewers made perceptual judgements about SFM stimuli, under unequal pay-offs. The results revealed an effect of reward size on early MEG responses in the region of the occipi- tal cortex and visual precuneus. Taken together, the experiments presented in this thesis provide consistent evidence that in- formation about reward can influence the processing of sensory information during perceptual decisions.
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Binge Eating Disorder : Neural correlates and treatmentsBrundin, Malin January 2019 (has links)
Binge eating disorder (BED) is the most prevalent of all eating disorders and is characterized by recurrent episodes of eating a large amount of food in the absence of control. There have been various kinds of research of BED, but the phenomenon remains poorly understood. This thesis reviews the results of research on BED to provide a synthetic view of the current general understanding on BED, as well as the neural correlates of the disorder and treatments. Research has so far identified several risk factors that may underlie the onset and maintenance of the disorder, such as emotion regulation deficits and body shape and weight concerns. However, neuroscientific research suggests that BED may characterize as an impulsive/compulsive disorder, with altered reward sensitivity and increased attentional biases towards food cues, as well as cognitive dysfunctions due to alterations in prefrontal, insular, and orbitofrontal cortices and the striatum. The same alterations as in addictive disorders. Genetic and animal studies have found changes in dopaminergic and opioidergic systems, which may contribute to the severities of the disorder. Research investigating neuroimaging and neuromodulation approaches as neural treatment, suggests that these are innovative tools that may modulate food-related reward processes and thereby suppress the binges. In order to predict treatment outcomes of BED, future studies need to further examine emotion regulation and the genetics of BED, the altered neurocircuitry of the disorder, as well as the role of neurotransmission networks relatedness to binge eating behavior.
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The neurobiological bases of compulsive eatingMoore, Catherine Frances 14 June 2019 (has links)
Compulsive eating behavior is a transdiagnostic construct that shares many behavioral, neurobiological, and theoretical features with compulsive drug use. The focus of this dissertation is to progress a framework for compulsive eating behavior, including identification of risk factors for its development and examination of functional neuroadaptations to brain reward systems in an animal model of compulsive eating.
We first investigated impulsivity (impulsive choice and impulsive action) as a potential vulnerability factor for the development of binge and compulsive eating behavior. Impulsivity has been implicated in drug addiction as well as eating disorders and obesity, but its exact role in the conferment of risk for compulsive eating is unknown. To achieve this, we measured impulsive choice (i.e. delay discounting) and impulsive action (i.e. motor impulsivity) and subsequent binge-like eating. We observed no effects of impulsive choice behavior on binge-like eating of palatable food; however, impulsive action predicted higher binge-like eating, higher motivation for palatable food, and increased compulsive-eating behavior. Therefore, impulsive action, but not impulsive choice, predicted the development of binge- and compulsive-like eating behaviors.
The second aim of this dissertation was to investigate functional neuroadaptations to brain reward pathways in rats with a history of palatable diet alternation, a model of compulsive eating. Overeating of palatable food, similar to exposure to drugs of abuse, is hypothesized to cause reward deficits via downregulation of mesolimbic dopamine systems. To investigate this, we measured sensitivity to d-Amphetamine using behavioral and neurochemical methods. To identify potential neuroadaptations to the dopamine and dopamine transporter (DAT) systems, we assessed baseline NAc-shell dopamine and DAT function in vivo. In rats with a history of palatable diet alternation, we observed deficits in the stimulating, reward-enhancing, and rewarding effects of d-Amphetamine, and impaired d-Amphetamine-induced dopamine efflux in the NAc-shell. Furthermore, dopamine and dopamine transporter systems were downregulated evidenced by decreased extracellular NAc-shell dopamine at baseline and decreased DAT function.
These results contribute to an overall framework for compulsive eating behavior where initial impulsivity predisposes compulsive eating and compulsive eating results in the emergence of reward deficits. / 2021-06-14T00:00:00Z
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Mesolimbic Dopamine Involvement in Pavlovian and Operant Approach BehaviorsMorvan, Cecile I. January 2010 (has links)
Thesis advisor: Jon C. Horvitz / Previous research has yielded conflicting results regarding the involvement of mesolimbic dopamine in Pavlovian and operant tasks. While there is abundant evidence that an operant lever press requires intact dopamine (DA) D1 transmission in the nucleus accumbens (ACB) and in the basolateral amygdala (BLA), there is conflicting evidence regarding the specific brain sites at which DA mediates a Pavlovian approach response. The present study was designed to compare the effects of ACB and BLA D1 receptor-blockade on an operant and Pavlovian task, while minimizing differences in behavioral response topography. Animals were trained on either a Pavlovian cued approach task or an operant cued nosepoke task. In the Pavlovian approach task, a tone signaled a pellet delivery to which animals responded with a head entry into a food compartment. In the operant nosepoke task, animals were trained to emit a nosepoke in response to the same tone, in order to trigger a pellet delivery. Bilateral microinfusions of the D1 antagonist SCH 23390 (0, 1 or 2 microgram/side) into either the ACB or the BLA produced a dose-dependent disruption of the operant nosepoke. In contrast, the Pavlovian cued approach response was unaffected by D1 antagonist microinfusions into either the ACB or the BLA. In addition, infusion of SCH 23390 into either site suppressed general locomotion. The results suggest a dissociation of the anatomical substrates mediating an operant nosepoke and a Pavlovian approach, despite similar response topographies. These findings are consistent with the notion that D1 activity at the ACB and BLA plays a role in the expression of operant responses, but not in the expression of Pavlovian approach responses. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Psychology.
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Belöningssystemets motiverande påverkan : Monetära eller icke-monetära belöningar? / The reward system´s motivational impact : Monetary or non-monetary rewards?Vehkamäki, Sebastian, Thodal, Emil January 2019 (has links)
Abstract Employees can be seen as the most important asset in order to reach the companies goals. In order to motivate employees to perform align with companies goal and visions reward systems could be used as a management tool. Reward systems could be used as a motivational tool and could also be seen as a system for recruitment, to inform and also to maintain commitment amongst employees, which contribute companies being a going concern. Difficulties while designing a well functional reward system is to adapt the system to all employee’s individual preferences and experiences, as a good motivational reward system builds on the fact that it motivates the employee. Previous research shows that different underlying factors affects the way employees respond to different rewards. As previous research has been done in specific industries, the ability to generalize to other industries is limited. The study aims to bring knowledge around the ways managers and management within industrial organizations motivate their employees and how different reward systems later on affects the employee’s motivation. To investigate this, a quantitative survey of employees in industrial companies has been carried out and based on previous research and theory on reward systems, presumable connections have been studied to answer the formulated questions. The results of the study indicate that underlying factors have some impact on which rewards are valued. The results can be partly supported in previous research, but there are also differences like women value monetary rewards equally high as men. The study increases the knowledge of how employees are motivated in the industrial sector, and leads to greater knowledge about how managers and management can work with reward systems. Keywords: reward system, motivation, underlying factors, industry / Sammanfattning Anställda kan ses som den viktigaste tillgången för att kunna prestera och uppnå företagens mål. För att lyckas få medarbetare motiverade till att prestera i enlighet med företagens mål och vision kan belöningssystem användas som styrverktyg. Belöningssystem kan öka anställdas motivation till att prestera, det kan även ses som en faktor för att rekrytera, informera och behålla engagemang hos medarbetare, vilket bidrar till företagens fortlevnad. Svårigheter med att forma ett passande belöningssystem är att anpassa systemet till anställdas preferenser och erfarenheter. En bra belöning bygger på att den anställde värdesätter den. Tidigare studiers resultat har visat att bakomliggande faktorer påverkar hur anställda värdesätter belöningar. Dessa studier är gjorda i specifika branscher vilket resulterar i att generaliserbarheten till andra branscher är begränsad. Studien syftar till att påvisa samt bringa kunskap kring hur chefer och ledning inom industriorganisationer motiverar sin personal och sina anställda samt hur anställda sedermera upplever sig motiverade av organisationernas belöningssystem. För att undersöka detta har en kvantitativ enkätundersökning hos anställda inom industriföretag genomförts. Utifrån tidigare forskning samt teori kring belöningssystem har presumtiva samband undersökts för att besvara frågeställningarna. Studiens resultat indikerar att bakomliggande faktorer har viss påverkan på vilka belöningar som värdesätts. Resultatet kan delvis stödjas i tidigare forskning, dock finns även skillnader som att kvinnor värdesätter monetära belöningar i lika hög grad som män. Studien ökar kunskapen om hur anställda motiveras inom industribranschen, och utmynnar i större kunskap kring hur chefer och ledning kan arbeta med belöningssystem. Nyckelord: belöningssystem, motivation, bakomliggande faktorer, industribransch
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Alterações na perfusão cerebral de obesos após administração de 75 gramas de glicose. Estudo com SPECT, controlado, cego e aleatorizado / Cerebral perfusion changes in obese subjects after administration of 75 grams of glucose. A SPECT, controlled, blinded and randomized studySilva, José Henrique da 20 March 2015 (has links)
RACIONAL: A obesidade caracteriza-se por um excesso de tecido adiposo branco que causa morbidades metabólicas, mecânicas e a morte de aproximadamente 2,8 milhões de pessoas anualmente. Sua fisiopatologia envolve alterações em mecanismos que interagem no cérebro, sejam humorais, neurais e comportamentais, os quais podem ser eliciados por alimentos. Por sua vez, técnicas de neuroimagem funcional, como o Single-photon Emission Tomography (SPECT), surgiram como ferramentas para avaliar alterações funcionais in vivo. Por isso, questionamos se imagens de SPECT cerebral, alteradas após a ingestão de glicose em comparação a um teste controle com água, explicariam, pelo menos em parte, o comportamento alimentar da obesidade. OBJETIVOS: Comparar a perfusão (ativação) cerebral de imagens de SPECT, após ingestão de água vs. glicose, em mulheres obesas e com peso normal. Correlacionar a intensidade da perfusão encontrada com níveis sanguíneos de leptina, insulina e glicemia, bem como com a quantidade de gordura corporal. MATERIAIS E MÉTODOS: 10 mulheres com e 10 sem obesidade (n = 20) foram submetidas à SPECT cerebral duas vezes, após marcação pelo [99mTc]-ECD 30 minutos após ingestão de 300 mL de água e de uma solução com 75 gramas de glicose, em dias separados (40 SPECTs), tendo sido cada sujeito controle de si mesmo. As imagens foram comparadas intragrupo e entre grupos por meio do software Statistical Parametric Mapping. Modelos de efeitos mistos foram usados para avaliar correlações entre as variáveis. RESULTADOS E DISCUSSÃO: Mulheres obesas apresentam maior ativação em regiões da Default Mode Network e da Salience Network após o teste com água. Enquanto as obesas apresentam-se mais engajadas na percepção dos processos fisiológicos (como fome e sede) na situação basal, com água, apenas aquelas com peso normal parecem responder às alterações desses processos eliciadas pelo alimento oferecido. Após estímulo com glicose, apenas o grupo sem obesidade aumentou a perfusão em regiões relacionadas à recompensa e ao controle do comportamento, como corpo estriado e córtices orbitofrontal e pré-frontal. A perfusão nestas áreas apresentou correlação negativa com a interação entre leptina e insulina (Coef. = - 0,001, p = 0,003). Além disso, tais regiões recebem aferências dopaminérgicas e, por isso, temos como hipótese que déficits na sinalização da dopamina explicariam os achados encontrados. CONCLUSÃO: A ingestão de glicose eliciou respostas relacionadas à recompensa alimentar normal e a um controle apropriado sobre o apetite nas mulheres sem obesidade, não sendo observado o mesmo nas obesas, processo do qual parece participar a interação entre insulina e leptina e déficits na sinalização dopaminérgica. / RATIONALE: Obesity is an excess of white adipose tissue that causes mechanical, metabolic injuries and mortality of approximately 2.8 million people annually. Its physiology involves alterations in humoral, neural and behavioral mechanisms that interact in brain, which can be elicited by nutrients. Functional neuroimaging techniques, such as Single-photon Emission Tomography (SPECT), arise as tools to evaluate abnormalities in vivo. Therefore, we argue if changes in brain images, after intake of glucose, compared to a test with water, would explain, at least in part, the altered feeding behavior of obesity. OBJECTIVES: Compare perfusion (activation) of brain SPECT images after water vs. glucose intake in obese and normal weight volunteers. Correlate the intensity of perfusion found with blood levels of leptin, insulin and glucose, as well as with the amount of body fat. MATERIALS AND METHODS: 10 women with and 10 women without obesity (n = 20) underwent SPECT twice, after labeling by the [99mTc]-ECD 30 minutes after ingesting 300 ml of water and a solution of 75 grams glucose, on separate days (40 SPECTs) being each subject control of yourself. The images were compared between groups and intragroup using Statistical Parametric Mapping. Mixed effects models were used to assess correlations between variables. RESULTS AND DISCUSSION: Obese women have higher activation in regions of the Default Mode Network and Salience Network after test with water. While obese have become more engaged in the perception of physiological processes (such as hunger and thirst) at baseline, with water, this group do not seem to respond to changes of these processes elicited by the food offered. After glucose intake, only those with normal weight increased perfusion in regions related to food reward and behavioral control, such as striatum and orbitofrontal and prefrontal cortices. The perfusion in these areas was negatively correlated with the interaction between leptin and insulin (Coef = -. 0.001, p = 0.003). In addition, these regions receive dopaminergic afferents and therefore we hypothesized that deficits in dopamine signaling could explain the results observed. CONCLUSION: Glucose intake elicited responses related to normal food reward and the appropriate control over appetite in women without obesity, not being observed the same in obese volunteers, a process in which the interaction between insulin and leptin, as well as dopamine signaling seems to participate.
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Effort-Reward-Imbalance inom vården : samvarierar ansträngning-belöning, överengagemang med samarbetsförmåga och trivsel i arbetsgrupper?Immo, Sara, Tärnblom, Sofie January 2019 (has links)
Tidigare studier beskriver vikten av samarbete inom hela vårdsektorn för att skapa en patientsäker vård. En jämn arbetsbörda och tillräckligt med personal är också betydelsefullt. Denna studie undersökte balansen ansträngning-belöning, överengagemang och om det samvarierar med samarbetsförmåga och trivsel i arbetsgrupper inom vården. Genom att använda Effort-Reward-Imbalance model mättes balansen ansträngning-belöning samt överengagemang på arbetet. Via enkäter och intervjuer undersöktes även samarbetsförmåga och trivsel. Av totalt 148 enkäter var respondenterna 78 kvinnor, 12 män, och 8 annat. Respondenternas ålder var mellan 26-65 år. Fyra respondenter intervjuades. Studien visade att balansen ansträngning-belöning inte tycks spela någon roll för samarbetsförmågan i arbetsgruppen. Respondenternas subjektiva upplevelse mynnade ut i sex centrala teman. Respondenterna framförde vikten av att arbeta i team, vilket även tidigare forskning visat. Arbetstagare inom vården verkar uppleva ett gott samarbete och trivsel på sina arbetsplatser, vilket är motsatsen till dagens lägesrapporter. Studien ger därför en annan synvinkel på vårdyrket.
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Motivace žáků v hodinách tělesné výchovy na 1. stupni zákadní školy / Motivation of Elemntary School Pupils in Physical Education ClassesBartůňková, Alžběta January 2018 (has links)
This diploma thesis is focused on motivation of pupils in physical education classes at elementary school. Its aim is to find out how teachers motivate their pupils in PE classes and what response these pupils give to this motivation. In the theoretical part some terms and theories concerning motivation and its use in PE classes are mentioned. In the practical part, I focused on observing motivational elements in PE classes and their subsequent analysis. The research was carried out at two elementary schools - ZŠ Mníšek pod Brdy and ZŠ Stará Huť. It took place amongst pupils from 1st to 5th year.
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A mecânica do desejo no desencadeamento da ação no Leviatã de Thomas HobbesKayser, Marcos 18 December 2006 (has links)
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Previous issue date: 18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho analisaremos o conceito de desejo e seu desdobramento na teoria de Thomas Hobbes, identificando-o como um elemento fundamental na constituição do corpo, a partir da antropologia, ou psicologia empírica, desenvolvida por Hobbes, subvertendo a ordem tradicional do universo ético e político. Desejo que aparece como uma força, um impulso que dá movimento a vida, sinônimo de felicidade, mas que, por sua desmedida insaciabilidade, coloca o homem sob risco da morte prematura e violenta. Estado de conflito, representado pelo estado de natureza hobbesiano, no qual o homem, num contexto hipotético de pura igualdade, ataca por desejo, seja para obter mais e mais poder, seja para não perder o que possui. Por trás do medo da morte, há o medo da perda do objeto mais cobiçado, ou seja, a vida. Mas apesar do homem espreitar o inimigo e aparentar irracionalidade, é capaz do consenso, quando faz uso da razão, com a qual se somam vontade e eloqüência. O consenso é o pacto, que cria as condições de possibilidade p / In this study we will analyze the concept of desire and its implication in Thomas Hobbes’ Theory, identifying it as a fundamental element in the determination of the man’s action, through the anthropology or empiric psychology developed by Hobbes, changing the traditional order of the ethics and political universe. Desire that appears as a power, an impulse which gives movement to life, synonym of happiness, but, because it is without measure or satisfaction, puts man in situations where the risk of premature and violent death is present. State of conflict, represented by the hobbesian state of nature, in which man, in a context of pure equality, attacks for desire, either to obtain more and more power, or not to lose what he had already achieved. Behind the fear of death, there is the fear of losing the most desired object: life. But, despite spying the enemy, man is also capable of a consensus, when he uses his sense, with which he adds will and elocution. The consensus is the pact which creates the conditi
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Práticas de reconhecimento e recompensa no processo de inovação : estudo de caso em empresa do setor elétricoLederman, Mauricio January 2016 (has links)
A cultura da Inovação é algo almejado pelas organizações para a melhoria de desempenho e de sua vantagem competitiva. Num ambiente de regulação, onde a inovação é tema obrigatório, caso do setor elétrico por exemplo, passa a ser fundamental o tratamento diferenciado a este processo. No entanto, a inovação deve ser estruturada de forma que as práticas de gestão de pessoas permitam que se crie um ambiente de desenvolvimento organizacional, pois ele é um pilar importante na construção de uma cultura de inovação. A integração entre estes dois processos, portanto, torna-se fundamental e, nesse sentido, este trabalho tem como objetivo geral de Propor a integração dos processos de gestão de pessoas e inovação no Grupo CEEE e, para isso, tratou-se como objetivos específicos em dois artigos, sendo: (i) propor diretrizes para a gestão da inovação do Grupo CEEE a partir da análise das práticas de gestão de pessoas; e (ii) estruturar um programa de reconhecimento e recompensas visando o incentivar o processo de inovação Trata-se de dois estudos de caso, de natureza aplicada qualitativa exploratória, no intuito de levantar o máximo de informações acerca dos temas, tendo como principal contribuição preencher uma lacuna identificada na gestão da inovação da empresa em estudo, mas servindo também como exemplo para as demais empresas do setor de energia. Como resultados deste trabalho, foi possível propor alternativas nos processos de gestão de pessoas visando o desenvolvimento de uma cultura de inovação, além de também, propor uma metodologia visando o reconhecimento e a recompensa no processo de inovação, pilar importante do processo de gestão de pessoas para desenvolver uma cultura de inovação. Uma vez implementada estas propostas, será possível perceber a integração destes dois processos, permitindo a empresa obter ganhos em todas as dimensões da inovação, atendendo ao proposto no objetivo geral. / The culture of innovation is something pursued by organizations to improve performance and competitive advantage. In an environment regulated, where innovation is required subject, in the case of the electricity sector for example, it becomes fundamental differential treatment in this process. However, innovation must be structured so that personnel management practices allow you to create an organizational development environment because it is an important pillar in building a culture of innovation. The integration between these two processes, so it is essential and in this sense, this work has as main objective to propose the integration between the personnel management processes and innovation in CEEE Group and, therefore, treated as specific goals in two articles, namely: (i) personnel management practices in the Innovation Process; and (ii) Recognition and reward the Innovation Process. These are two case studies, exploratory qualitative applied nature, in order to get as much information about the themes with the main contribution to fill a gap identified in the company's innovation management study, but also serving as an example to other companies in the energy sector. As a result of this work, it was possible to propose alternatives in the personnel management process aiming the development of a culture of innovation, and also propose a methodology aiming to recognize and reward the innovation process, important pillar of personnel management process to develop a culture of innovation, Once implemented these proposals, it will be possible to realize the integration of these two processes, enabling the company to obtain gains in all dimensions of innovation, given to the overall objective.
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