Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-06-06T13:40:38Z No. of bitstreams: 1 Mariana Delgado Monteiro de Araújo_.pdf: 590386 bytes, checksum: 741b396888189af9f91c2c70cc2b86c7 (MD5) / Made available in DSpace on 2017-06-06T13:40:38Z (GMT). No. of bitstreams: 1 Mariana Delgado Monteiro de Araújo_.pdf: 590386 bytes, checksum: 741b396888189af9f91c2c70cc2b86c7 (MD5) Previous issue date: 2017-03-28 / Nenhuma / As redes sociais estão sendo utilizadas para realizar trabalhos colaborativos, utilizando a inteligência das multidões. Todos podem colaborar com ideias sem importar quando o farão ou a que distância estão. Nessa lógica, surgem iniciativas como o crowdsourcing, para resolução de problemas ou promoção de inovações, e o crowdfunding, para arrecadar recursos financeiros para iniciativas com fins específicos. Uma vez que os projetos de crowdfunding apresentam resultados de sucesso e insucesso dentro das plataformas existentes, o presente trabalho tem como tema as recompensas como estratégias para o sucesso de projetos de crowdfunding. O objetivo principal é compreender quais estratégias de recompensas se tornam diferenciais em projetos exitosos de crowdfunding, tendo como objeto de estudo as recompensas dos projetos de crowdfunding da plataforma Catarse. O estudo apresenta, em sua fundamentação teórica, os temas das multidões e crowdsourcing, crowdfunding e as recompensas como estratégias. Como caráter exploratório, o estudo utilizou a Análise Qualitativa Comparativa (QCA) valendo-se da Lógica Crisp-Set e da Lógica Fuzzy-Set para análise. Dentre os resultados da pesquisa, destacam-se estratégias que contribuem para o sucesso do projeto, sendo elas: exclusividade, pré-compra e co-criação. Além disso, os resultados demonstram a necessidade de outros fatores para o sucesso do projeto. A identificação desse comportamento das estratégias de recompensas promove uma contribuição teórica à medida que aprofunda o estudo sobre as recompensas dos projetos, já que a temática é pouco explorada. Adicionalmente, os resultados da pesquisa apresentam orientações para que os empreendedores possam construir suas recompensas com base em estratégias que contribuam positivamente para o resultado. / Social networks are being used to perform collaborative work using the intelligence of the crowds. Everyone can collaborate with ideas anytime from anywhere. In this logic initiatives arise as crowdsourcing to solve problems or promote innovations, and crowdfunding to raise funds for specific purpose initiatives. Crowdfunding projects present successful and unsuccessful results within existing platforms. The present theme is about rewards as strategic for the success of crowdfunding projects. The main objective is to understand which rewards strategies become differential in successful crowdfunding projects, having as an study object the rewards of the crowdfunding projects of the Catarse platform. In its theorical foundation the study addresses issues such as the crowds, crowdsourcing, crowdfunding and rewards as strategy assets. With an exploratory character, this study used the Comparative Qualitative Analysis (QCA) with the Crisp-Set Logic and the Fuzzy-Set Logic for analysis. Among the research results stand out strategies that are mainly associated with successful projects , exclusivity, pre-purchase and co-creation. Besides, research results show that are they necessary other success project factors The identification of this results provides a theoretical contribution As the theme of reward strategy is little explored. In addition, the research results provide guidelines for entrepreneurs to build their rewards based on strategies that contribute to the outcome.

Curiosity drives many of our daily pursuits and interactions; yet, we know surprisingly little about how it works. Here, I harness an idea implied in many conceptualizations of curiosity – that information has value in and of itself. Reframing curiosity as the motivation to obtain reward – where the reward is information – allows me to leverage major advances in theoretical and computational mechanisms of reward-motivated learning. Using willingness to wait, an established measure of reward-motivated behavior, I test the reward value of information, finding that people are more willing to wait for information about which they’re more curious. I then provide new evidence supporting several predictions that emerge from this information-as-reward framework. In Chapter 1, I examine whether the valence of information affects its reward value, finding an asymmetric effect of positive vs. negative information, with positive valence associated with both enhanced curiosity and enhanced long-term memory for information. I then test an idea drawn from computational and neurobiological accounts of reward learning, which suggest that it is not the absolute value of information that drives learning, but, rather, the gap between the reward expected and the reward received. By asking people to rate both their curiosity about a question and their satisfaction with the answer, I obtain measures of the values of the reward expected (curiosity) and the reward received (satisfaction) and find that the discrepancy between the two – the information prediction error – facilitates learning. These findings suggest a conceptual correspondence between dopaminergic mechanisms of reward learning and curiosity. Aging is associated with decrements in dopaminergic functioning, but it is unclear whether these deficits extend to curiosity, as few behavioral investigations of curiosity and aging exist. In Chapter 2, I, therefore, sought to explore the effects of aging on curiosity, providing behavioral evidence that curiosity is not diminished in aging, but, rather, that it is enhanced. These findings also revealed that older adults are more likely to wait for more positive information, consistent with existing theories of emotional processing. In Chapter 3, I sought to test whether the dopaminergic reward system, particularly the striatum, plays a necessary and causal role in curiosity by examining curiosity in patients with Parkinson’s disease, a neurological disorder characterized by dopamine depletion in the striatum and striatal dysfunction. I provide evidence for diminished curiosity in people with Parkinson’s disease, relative to age- and education-matched controls. In particular, I find that participants with Parkinson’s disease are less likely to wait for lower-value rewards, i.e., information about which they’re less curious. Taken together, these results support the idea that information functions as a reward – much like money or food – guiding choices and driving learning in systematic ways.

The ability to find positive meaning and in turn generate positive emotions in the face of negative life circumstances is a protective factor against the harmful effects of stress, and a critical pathway to resilience and growth. Despite its clear importance, little is known about the brain mechanisms that support this ability, the processes that underlie decisions to implement it, or the long-term effects it has on memories of negative life experiences. Study 1 shows that finding positive meaning in negative experiences engages the brain’s system for reward valuation, whereas minimizing negative emotions dampens activity in a region involved in generating emotional arousal. Study 2 shows that spontaneous brain responses to aversive stimuli can be used to prospectively predict decisions to regulate emotion, and the predictive value of these responses is comparable across finding positive meaning and minimizing negative emotions. Study 3 shows that finding positive meaning and minimizing negative feelings can bring about distinct lasting effects on the content and affective impact of memories of negative experiences.

Cette thèse a étudié l’interaction entre l’obésité induit par la diète et la physiologie fcHFHS) avec un régime gras et sucrée ou un régime normocalorique chez la souris et le rat. Le régime fcHFHS a modifié le profile journalier de prise alimentaire et l’expression de la protéine PER2 dans l’habenula latérale (LHb) chez la souris. Cependant chez le rat, ni la prise alimentaire ni l’expression du gène Per2 dans la LHb n’ont changé, mais des altérations ont été observées dans le noyau accumbens. Chez les rats nourris avec une diète standard ou fcHFHS, le blocage glutamatergique dans la LHb induit une altération de la prise alimentaire dépendant du temps du blocage. Finalement, nous avons étudié le comportement alimentaire chez des souris contrôle et mutantes du gène horloge Npas2 nourris avec le régime fcHFHS. Le comportement alimentaire, néanmoins, était similaire entre les deux génotypes. Les résultats indiquent une relation entre le type de diète et une expression anormale des gènes horloges dans le circuit de la récompense, ainsi comme un rôle important de la LHb dans la prise alimentaire. / This thesis studied the interaction between diet-induced obesity and the 24h variations in behavior and physiology paced by the circadian system. Mice and rats were fed with a free choice high-fat high-sugar diet (fcHFHS). In mice, fcHFHS diet changed day-night eating patterns and PER2 clock-protein expression in the Lateral Habenula (LHb), a food-reward related area. In rats, no feeding patterns or clock-gene changes in LHb were found, however, Per2 gene expression was disrupted in the Nucleus Accumbens, which is indirectly connected to LHb. When blocking pharmacologically the glutamatergic functioning of the LHb, food intake was altered in both chow and fcHFHS-fed rats in a time-dependent manner. Finally, we tested the influence of Npas2 clock-gene on the disruption of rhythmic behavior produced by the fcHFHS-diet using Npas2 mutant and WT mice. Both genotypes, however, displayed similar altered eating patterns caused by the fcHFHS diet. Our findings indicate a relationship between nutrient type and an abnormal clock-gene expression in food reward-related areas, and an important role for the LHb in feeding behavior.

Nicotine is one of the most addictive drugs known to man, yet it has limited reinforcing effects in humans and non-human animals when it is not self-administered in tobacco products. One hypothesis for these paradoxical effects of nicotine is that the effects of the drug in the brain alter acquisition of incentive learning. The hypothesis for this study is that nicotine will increase the value of cues paired with a reward. To test this hypothesis, 26 Sprague Dawley Male rats were randomly assigned to one of three groups Pre-NIC (the critical experimental group), Post-NIC and SAL. Each group received a subcutaneous injection 15 min prior to testing and another injection 1-3 h after testing. For the Pre-NIC group, nicotine (0.4 mg/kg base) was injected 15 min before test sessions; placebo was administered after testing. For the Post-NIC group the order of injections was reversed, and this manipulation controls for total exposure to nicotine. The SAL groups received placebo injections before and after testing. Rats were shaped to respond for 10% sucrose for pressing an illuminated nose-key (Experiment 1) or 0.2% saccharin for pressing a lever (Experiment 2). Responding in the Pre-NIC group was higher than all other groups in Experiment 2 (saccharin reward); however, responding in the three groups was similar in Experiment 1 (sucrose reward). This paradigm highlights how nicotine can increase motivation for rewards, but that the facility of operant behaviors and caloric value of the reward may mask this effect.

The purpose of this study was to review the existing teams research which suggests that teams vary along 4 dimensions of interdependence. Task interdependence is the extent to which the task drives interactions among individuals. Resource interdependence is the extent to which individuals rely on others to provide inputs necessary to complete their portion of work. Reward interdependence is the extent to which individuals' rewards are tied into the performance of others. Finally, goal interdependence is the extent to which individuals set goals and receive feedback at the group versus individual level. A comprehensive team interdependence scale tapping into these 4 distinct dimensions was developed and tested in a cross organizational sample. Factor analytic results suggested that a 4-factor model did indeed provide the best fit for the data. A discussion of the findings, implications, limitations, and future directions is presented.

Background: Approximately 7% of clinically referred youth exhibit profound impairment in the ability to regulate their affect, behavior, and cognition. This phenotype – often referred to as dysregulation – has been associated with a multitude of negative outcomes. Symptom overlap between dysregulation and other psychological disorders has generated debate regarding whether DP constitutes a distinct syndrome characterized by intense, persistent irritability or is merely the combination of symptoms from disruptive or mood disorders. In order to elucidate this question, the current study examined the transdiagnostic continuities and discontinuities in three RDoC constructs (frustrative non-reward, acute threat, and cognitive control) proposed to be mechanisms of irritability Method: Participants were 294 children ages 7-17 (M=10.94; 67% male). Emotional and behavioral symptoms were measured using the Child Behavior Checklist and the Kiddie Schedule for Affective Disorders and Schizophrenia. Frustrative non-reward was measured using a frustration-induction Go/No-Go paradigm during which heart rate variability was indexed by respiratory sinus arrhythmia (RSA) and pre-ejection period (PEP). Acute threat was measured using an Emotional Faces computer paradigm in conjunction with an eyetracker/pupilometer. Cognitive control was assessed with the Behavioral Rating Inventory of Executive Function (BRIEF), Delis-Kaplan Executive Function System (D-KEFS) and Stop Signal Task (SST). Results: Symptoms of dysregulation and non-episodic irritability were strongly, positively related. Due to a lack of demonstrated construct validity for the hypothesized RDoC constructs of frustrative non-reward, acute threat, and cognitive control, two alternative mechanisms—SNS response and cognitive dyscontrol of emotion—were derived from the data. Results showed that blunted sympathetic responsivity and poor executive control in response to emotion were predictive of more severe irritability symptoms. Finally, moderation analyses showed that among highly dysregulated children, low levels of sympathetic responsiveness were associated with more severe irritability symptoms. Conclusions: Despite phenotypic overlap with other forms of developmental psychopathology, dysregulated children can be distinguished based on the severity of their irritability symptoms. This supports the conceptualization of dysregulation as a unique syndrome characterized by intense and persistent irritability and lends credence to the novel diagnosis of DMDD. Furthermore, cognitive, behavioral and physiological patterns identified in this study suggest that difficulties with processing negative emotion—as opposed to frustration or threat specifically—may constitute a vulnerability for irritability.

The environment is abundant with visual information. Each moment, this information competes for representation in the brain. From billboards and pop-up ads to smart phones and flat screens, in modern society our attention is constantly drawn from one salient object to the next. Learning how to focus on the objects that are most important for the current task is a major developmental hurdle. Fortunately, rewards help us to learn what is important by providing feedback signals to the brain. Sometimes, in adolescence for example, reward seeking can become the pre-potent response. This can ultimately lead to risky and impulsive behaviors that have devastating consequences. Until recently, little has been known about how rewards operate to influence the focus of attention. In this document, I first demonstrate the robustness of various behavioral paradigms designed to measure reward processing in vision. I found that even mundane rewards, such as images of money, are effective enough to prime the attentional system on the basis of value. Remarkably, this effect extended to images of Monopoly money. This observation suggests that whole classes of visual stimuli, such as food, pornography, commercial logos, corporate brands, or money, each with its own reward salience value, are likely vying for representation in the brain. This work has implications for the growing digital economy as it suggests that novel value systems, such as the digital currency Bitcoin, could eventually become as psychologically relevant as physical currency provided sufficient use and exposure. Likewise, this work has implications for gamification in the industrial setting. Next, I examined the sensitivity of the system to make optimal economic decisions. When faced with an economic choice normative theories of decision-making suggest that the economic actor will choose the response that affords the greatest expected utility. Contrary to this account, I developed a new behavioral paradigm (reward contingent capture) and reveal that the attentional homunculus is a fuzzy mathematician. Specifically, I found that low-level attentional processes conform to the same probability distortions observed in prospect theory. This finding supports a unified value learning mechanism across several domains of cognition and converges with evidence from monkey models. Then, I demonstrate the influence of rewards on high-order search parameters. I found that images of money can implicitly encourage observers to preferentially adopt one of two search strategies – one that values salience versus one that values goals. Together, my results expose two distinct ways in which the very same rewards can affect attentional behavior – by tuning the salience of specific features and by shaping global search mode settings. Lastly, I draw from my empirical results to present a unified model of the manifold role of rewards on visual attention. This model makes clear predictions for clinical applications of rewarded attention paradigms because it incorporates a dimension of complexity upon which learning processes can operate on attention. Thus, future work should acknowledge how individual traits such as developmental trajectory, impulsivity, and risk-seeking factors differentially interact with low- and high-level attentional processes. In sum, this document puts forward the notion that rewards serve a compelling role in visual awareness. The key point however is not that rewards can have an effect on attention but that due to the nature of visual processing, reward signals are likely always tuning attention. In this way we can consider reward salience an attentional currency. This means then that deciding where to attend is a matter of gains and losses.

Repeated exposure to drugs of abuse conditions individuals to anticipate the behavioral consequences of drug use specifically in the presence of a drug-associated context. In rodents, preferences and aversions for alcohol and cocaine have been conditioned; however, the mechanisms underlying the expression of these conditioned effects remain unknown. Given that alcohol and cocaine polysubstance abuse is prevalent in young individuals, with more than 50% of these polysubstance abusers reporting to be under the age of 21, it is important to understand the mechanisms contributing to the behavioral effects of alcohol and cocaine co-dependency. Aim 1 determined if age differentially impacted the effects of repeated alcohol exposure on conditioned cocaine preferences. Adolescent [postnatal day (PND) 30) and adult (PND 60) male Sprague-Dawley rats were administered ethanol (0.5 or 1.75 g/kg, i.p.) immediately before each cocaine conditioned place preference (CPP) session (20 mg/kg, i.p.; 15 minutes). Aim 2, Experiments 1 and 2, identified the role of NMDA receptors within the nucleus accumbens septi (NAcc) in conditioned ethanol/cocaine behavior. Adolescent and adult rats in Experiment 1 were administered the NMDA antagonist MK-801 (0.1 or 0.2 m/kg, i.p.) 30 minutes prior to cocaine conditioning. Adolescent and adult rats within Experiment 2 underwent bilateral cannulation for chronic implantation of the cannulae into the NAcc of both hemispheres. Rats administered 1mM MK-801 or saline into the NAcc prior to cocaine (20.0 mg/kg, i.p.) conditioning, completed additional testing to determine the role of NAcc NMDA receptors in the consolidation, reconsolidation and expression of cocaine conditioned behavior in a drug-induced reactivation manner. Findings show adolescent and adult rats responded similarly to co-administration of ethanol/cocaine with both ages showing a decrease in the rewarding properties of cocaine. What differed between the age groups were the aversive properties of ethanol, with adolescents being less sensitive to the aversive properties of ethanol and its modulating effects on cocaine reward. A role for the NAcc NMDA receptors was observed in contributing to the modulating effects of ethanol on cocaine reward. Lastly, the reconsolidation of cocaine reward was more sensitive to disruption in adolescent rats, as compared to their adult counterparts. These results suggest an increased vulnerability for adolescents to continue engaging in polysubstance abuse. However, this at-risk age group also appeared to be more responsive to pharmacological treatment in decreasing addictive behavior.

This thesis details a continuing body of research investigating the contribution of personality to disordered eating and alcohol abuse in young women. There is growing evidence of high levels of reward sensitivity in women with both disorders, and high levels of punishment sensitivity in dysfunctional eating women. However, it is unlikely that personality alone accounts for the development of such dysfunctional behaviour. Two studies were conducted to further examine the contribution of reward and punishment sensitivity to these disorders. In the first study, 443 university women completed self-report measures of alcohol use, dysfunctional eating, reinforcement sensitivity, parental drinking, family environment and maternal eating. Reward and punishment sensitivity were better predictors of disordered behaviour than family factors, although maternal dysfunctional eating significantly increased the risk of daughters' dysfunctional eating. Punishment sensitive daughters of bulimic mothers reported the highest level of bulimic symptoms themselves. Punishment sensitivity also functioned as a partial pathway variable between family risk and disordered eating. Given the stronger contribution of personality to disordered behaviour, a second study was conducted in which 131 women completed behavioural tasks under conditions of reward and punishment. Performance on a computerised measure of punishment sensitivity was associated with greater levels of dysfunctional eating but not drinking. However, performance on a card-sorting task of reward sensitivity failed to correlate with self-reported reward sensitivity or disordered behaviour. It was concluded that an innate sensitivity to reward increases the risk of disorders characterised by strong approach tendencies, whilst high punishment sensitivity, perhaps due to a chaotic family, increases the risk of dysfunctional eating, particularly daughters of eating disordered mothers.