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Regulatory Focus Modulates Reward-Related Neural ActivityMowrer, Samantha M. 08 September 2009 (has links)
No description available.
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The Effect of Experimenter's Warmth/ Coldness on Intrinsic MotivationGuikema, Phillip N. 01 January 1985 (has links) (PDF)
Individuals may approach an activity with either intrinsic motivation. Extrinsic motivational orientations are characterized by simplicity and predictability. Intrinsic motivation is characterized by novelty, complexity, and challenge. Task noncontingent rewards, in contrast to task contingent rewards, have been found to maintain or foster increases in intrinsic interest in a task. One explanation of this effect is that additional nonspecific factors like the perceived warmth of the experimenter was positively correlated with the noncontingent reward condition. To test this assumption, second grade subjects played with a game of intermediate complexity in one of four conditions: "cold" instructor with contingent reward, "cold" instructor with noncontingent rewards, "warm" instructor with contingent reward, and "warm" instructor with noncontingent reward. In a subsequent free-choice period, simple, intermediate, and complex versions of the game, as well as other activities, were available. The "warm" instructor was expected to create a greater positive affect toward the task which was measured by the amount of time spent with the complex game during free-choice time. Contrary to expectations, no significant difference was found between the four groups. Possible explanations of these findings are discussed.
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Prospective Role of Reward Responsiveness in Depression and Posttraumatic Stress Disorder Symptom Trajectories following Traumatic ExposureForbes, Courtney N. 15 September 2022 (has links)
No description available.
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⦁Engagera projektmedlemmar genom gamification? - En fallstudie gjord hos medieföretag i MalmöregionenPersson, Maria January 2017 (has links)
Uppsatsens syfte är att bredda kunskapen om begreppet gamification genom att studera hur medieföretag i Malmöregionen tar del av denna utveckling i sin interna verksamhet i deras projektgrupper som digitalt belöningssystem. Vid denna undersökning har en kvalitativ metod med kvalitativa intervjuer med tre medieföretag gjorts, samt en kompletterande kvantitativ innehållsanalys av insamlad data inom rådande ämnen. Av de trettionio som tillfrågades att medverka i studien blev det tre medieföretag vid namn Ozma, Adludo och 24HR som valde att delta. Samtliga medieföretag som intervjuades står inte främmande till de rådande ämnena i denna uppsats då de valts ut utifrån ett icke-sannolikhetsurval med tillhörande inklusionskriterier. Intervjuerna gjordes semistrukturerade hos medieföretagen eller på café. Resultatet av intervjuerna finns att erhålla under kapitel ”Resultat” för att sedan diskuteras tillsammans med den teorianknytning som gjorts till denna studie. Sammanfattningsvis har studien kunnat konstatera att problematiseringen som råder gällande att gamification är ett nytt begrepp i många olika sammanhang även kan ses i en bransch innehållande medieföretag som ändå har en viss kunskap om området. Ingen av de studerande medieföretagen använder sig av gamification i sin interna verksamhet, men samtidigt kan det ändå konstateras att ett visst intresse för denna typ ändå finns, vilket synes i undersökta medieföretags utbud av tjänster och produkter samt i det intervjumaterial som erhålls i denna studie. Medieföretagen i undersökningen använder sig heller inte av belöningssystem för att motivera medarbetare att engagera sig i den interna verksamheten likt projektarbeten då de anser att denna redan ligger på en tillfredställande nivå. Den mindre storleken på medieföretagen som skapar en familjär relation medarbetare emellan och det starka intresset för vad de gör på arbetsplatsen ser till att vara de främsta anledningarna, samt deras personliga sätt att ge uppskattning och feedback på ett ganska omedelbart och direkt sätt till vardera medarbetare som grupp. / The purpose of the study is to broaden the knowledge regarding the concept of gamification by studying how media companies in the Malmö region utilizes the approach, using it internally in their organizations as a reward system for their project groups. As part of the study, a qualitative method with qualitative interviews on three different organizations has been conducted, along with a complementary quantitative content analysis of collected data from relevant topics. From the 39 companies, initially asked to partake in the study, the three media companies Ozma, Adludo and 24H chose to participate. All media companies interviewed are not foreign to the different topics discussed in the paper since they were selected from a non-probability sample with associated inclusion criteria. The interviews were semi-structured and conducted either directly at the media company or at a café. The result of the interviews can be found in the “Resultat” chapter, and is further discussed together with the theoretical connections carried out within this study. In summary, the study could observe current problems caused by gamification, as a relative new concept, where fully utilizing the application is not straight forward, even in the media industry. None of the studied companies uses gamification internally in the organization although a clear interest could be seen in the products offered by the studied company, something also confirmed by the conducted interviews. The studied companies does also not use any reward systems to motivate and engage their employees in the organization such as in project groups, since they believe their employees already have a satisfactory level of motivation. The small size of the companies that creates a familiar and close relation between employees, and the strong interest in their tasks seem to be the primary reason behind the motivation, along with their personal way of give appreciation and feedback on a relatively immediate and direct manner towards each employee and group.
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Examining the relationship between cognitive control and nonsuicidal self-injuryBurke, Taylor Adele January 2019 (has links)
Nonsuicidal self-injury (NSSI), the deliberate self-destruction of one’s own body tissue engaged in without associated suicidal intent, is a prevalent behavior among adolescents and young adults. The current study examined whether one aspect of cognitive control, inhibitory control in response to negative emotional stimuli, is associated with repetitive engagement in NSSI. It further sought to examine whether sleep deficiency/irregularity, stress, and reward sensitivity moderate this relationship. A multi-method approach (self-report, behavioral measures, actigraphy) was employed to sensitively probe these relationships among 114 late adolescents with and without a history of repetitive NSSI. Findings suggested no relationship between inhibitory control in response to negative emotional stimuli and NSSI, as measured by a behavioral measure, but a significant positive relationship as measured by self-report. Stress and sleep irregularity, but not sleep deficiency or reward sensitivity, were associated with NSSI group status. Interaction analyses suggested that sleep irregularity and stress moderated the relationship between inhibitory control in response to negative emotional stimuli and NSSI. Results are discussed in terms of conceptual and clinical implications. Findings highlight the necessity of examining the temporal dynamics between the study’s constructs and NSSI by employing an ecologically valid approach. / Psychology
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Investigations into the Role of Orexin (Hypocretin) and Dynorphin in Drug Seeking, Reinforcement, and WithdrawalGentile, Taylor Arthur January 2018 (has links)
Psychostimulant dependence remains a major health and economic problem, leading to premature death and costing $181 billion annually in health care, crime, and lost productivity costs. Currently, no pharmacotherapies are available to effectively treat psychostimulant dependence. Psychostimulants cause changes in neural circuits involved in reward and affect, but addiction neurocircuitry is incompletely understood and new targets for therapeutic intervention are needed. Lateral hypothalamic orexins (hypocretins) have been shown to have functional roles in arousal, reward processing, attention, motivation, and impulsivity. The opioid peptide dynorphin, co-localized with orexin, has critical roles in producing negative affective emotion states through interactions with, among others, stress circuitry. Orexin-dynorphin neurons project to neural substrates governing positive and negative motivated behavior, including the bed nucleus of the stria terminalis (BNST), amygdala, locus coeruleus and ventral tegmental area (VTA). Orexin and dynorphin modulate post-synaptic membrane activity through opposing signaling mechanisms; while orexins bind to predominantly excitatory orexin-1 and -2 G-protein coupled receptors, dynorphins bind to predominantly inhibitory G-protein coupled kappa opioid receptors (KORs). Multiple psychopathologies, including anxiety and substance abuse disorders, are characterized in part by alterations in orexin-dynorphin signaling. While these peptides have been shown to co-localize within single presynaptic vesicles and exert opposing effects on post-synaptic membrane potentials, the utility of producing oppositely-behaving peptides and the implications on psychopathologies remains unknown. The present studies were conducted to explore the role of orexin and dynorphin activity in cocaine’s rewarding effects as well as the negative effects of withdrawal. To accomplish this, we measured 1. Effects of orexin and cocaine administration on impulsive behaviors that increase the likelihood of psychostimulant addiction, using 5-choice serial reaction time task in concert with systemic and site directed pharmacology. 2. Effects of orexin and dynorphin on motivation for cocaine administration and intracranial self-stimulation. Using immunohistochemistry, ultrasonic vocalizations, and fast scan cyclic voltammetry we explored possible dopaminergic mechanisms of orexin and dynorphin contributions to reward. Lastly 3. Effects of orexin, dynorphin and chronic cocaine on withdrawal-induced anhedonia using intracranial self-stimulation, elevated plus maze, and correlations with immunohistochemistry and plasma corticosterone levels to explore further mechanisms. The results of this dissertation support our hypothesis that orexin receptor activity contributes to cocaine-induced impulsivity, motivation to self-administer cocaine and the reinforcing effects of psychostimulants. Dynorphin activity contributes to anhedonia and anxiety seen during drug abstinence after chronic exposure. Orexin and dynorphin exert these effects, in part, by modulating activity of dopaminergic neurons projecting from the ventral tegmental area to the nucleus accumbens. / Biomedical Sciences
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REWARD-RELATED BEHAVIORAL EFFECTS OF PRESCRIPTION OPIOIDS AS A FUNCTION OF PUTATIVE ACUTE AND CHRONIC PAIN-LIKE STATES IN MALE AND FEMALE C57BL/6 MICENeelakantan, Harshini January 2014 (has links)
Pain is a leading cause of disability and the most common reason for clinical care. The field of pain research has focused on sex differences in the recent years with an expansive body of literature demonstrating sex-related differences in pain behavior and responsiveness to pharmacological interventions. Prescription opioids are potent analgesics and the mainstay for the clinical management of moderate-to-severe acute and chronic pain conditions. However, the long-term clinical use of prescription opioids for chronic pain remains controversial due to concerns about severe adverse effects, including tolerance, dependence, and addiction associated with opioid use. The non-medical use and abuse of prescription opioids has become a public health crisis, the problem even arising in a subset of chronic pain patients receiving opioid therapy. The vulnerability factors, specifically the role of pain in the propensity to prescription opioid abuse, are poorly understood. The present research project sought to investigate the propensity to opioid reward as a function of pain in male and female mice by incorporating acute (acetic acid-induced) visceral nociceptive and chronic chemotherapy (paclitaxel)-induced peripheral neuropathic pain models. Sexually dimorphic variations in the sensitivities of mice to nociceptive and allodynic behaviors were initially assessed using the two putative pain models. Following that, the two prescription opioids, morphine and oxycodone were examined under both pain contexts and the capacity of the two prescription opioids to produce reward-related behavioral effects were measured using drug discrimination, conditioned place preference, and intravenous drug self-administration procedures. The presence of acute noxious state but not chronic pain selectively attenuated the discriminative stimulus effects of the prescription opioid, morphine in male mice. The magnitude of modulation of the stimulus effects of opioids by the acute noxious state were further observed to be inversely related to the relative intrinsic antinociceptive effectiveness of the two opioids in reversing the acute noxious state and sex-specific sensitivities of mice to opioid-induced antinociception. In contrast, while no change was observed in opioid-reward as a function of the acute noxious state in both sexes, the presence of paclitaxel-induced chronic pain opioid-selectively and dose-selectively enhanced the conditioned rewarding effect of morphine (0.3 mg/kg dose), and the effect was more pronounced in male relative to female mice. These data were further supported by the self-administration results, in that the reinforcing efficacy (breakpoints under progressive ratio (PR) responding) and the incentive-motivational salience of morphine significantly increased in the presence of chronic pain in male mice, while non-selectively increasing regardless of the presence/absence of pain in female mice. Overall, the converging empirical evidence presented here suggest that these models provide preclinical tools to further understand the overlapping neurobiology of pain and opioid abuse, the behavioral effects of prescription opioids, and advance the development of novel sex-specific pain therapeutics with low addiction liability. / Pharmaceutical Sciences
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CHEMOKINE MODULATION OF MDPV-INDUCED BEHAVIOR AND NEUROPLASTICITYOliver, Chicora January 2019 (has links)
Psychostimulant abuse is a major public health concern yet no FDA-approved medications exist. Synthetic cathinones (“bath salts”) are a class of psychostimulants that have emerged relatively recently worldwide. One synthetic cathinone, MDPV (3,4-methylenedioxypyrovalerone) is mechanistically similar to cocaine but is over ten times more potent, possesses high abuse potential, and is relatively understudied. Recent studies have revealed involvement of inflammatory proteins called chemokines in the rewarding effects of MDPV and the mechanistically similar drug, cocaine. We and others have shown that the chemokine-receptor ligand pair CXCL12-CXCR4 is recruited in the rewarding effects of cocaine and MDPV. Humans and animal models of cocaine addiction have dysregulated CXCL12 and the commercially-available CXCR4 antagonist, AMD3100, can reverse cocaine use and relapse in preclinical models of addiction. Specifically, AMD3100 reduces self-administration and reinstatement to cocaine-seeking with concomitant alterations in CXCL12 gene expression in the midbrain. Here, I employ several complementary methods to demonstrate that AMD3100 also reverses MDPV-elicited behaviors. I demonstrate that (i) AMD3100 reverses MDPV-induced hyperlocomotion, conditioned place preference (preclinical model of drug reward), self-administration and reinstatement to MDPV-seeking behavior; (ii) AMD3100 can rescue MDPV-induced deficits in measures of anxiety and recognition memory shortly after a binge; and (iii) repeated MDPV exposure upregulates CXCL12 gene expression in the nucleus accumbens with concomitant downregulation of dendrite morphometrics and a related synapse scaffolding protein gene expression. These findings implicate CXCR4-CXCL12 signaling in the modulation of MDPV-elicited behaviors, suggesting that AMD3100 is a viable therapeutic option for the effects of this synthetic cathinone. / Psychology
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Software rejuvenation in cluster computing systems with dependency between nodesYang, M., Min, Geyong, Yang, W., Li, Z. 17 March 2014 (has links)
No / Software rejuvenation is a preventive and proactive fault management technique that is particularly useful for counteracting the phenomenon of software aging, aimed at cleaning up the system internal state to prevent the occurrence of future failure. The increasing interest in combing software rejuvenation with cluster systems has given rise to a prolific research activity in recent years. However, so far there have been few reports on the dependency between nodes in cluster systems when software rejuvenation is applied. This paper investigates the software rejuvenation policy for cluster computing systems with dependency between nodes, and reconstructs an stochastic reward net model of the software rejuvenation in such cluster systems. Simulation experiments and results reveal that the software rejuvenation strategy can decrease the failure rate and increase the availability of the cluster system. It also shows that the dependency between nodes affects software rejuvenation policy. Based on the theoretic analysis of the software rejuvenation model, a prototype is implemented on the Smart Platform cluster computing system. Performance measurement is carried out on this prototype, and experimental results reveal that software rejuvenation can effectively prevent systems from entering into disabled states, and thereby improving the ability of software fault-tolerance and the availability of cluster computing systems. / National Natural Science Foundation of China under the grant No. 60872044, 71133006, and Fundamental Research Funds for the Central Universities, and the Research Funds of Renmin University of China.
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Characterizing Reward Function During Social Feedback: Associations with Anhedonia in Socially Anxious AdolescentsCarlton-Smith, Corinne Nicole 05 May 2023 (has links)
The present study aimed to: (1) Characterize markers of reward sensitivity during periods of social stress using a well validated social feedback paradigm; (2) Evaluate clinical relations between reward markers and anhedonia; and (3) Investigate if elevated levels of baseline prior exposure to stress (i.e., peer victimization) are associated with the degree of ventral striatum suppression and anhedonia symptoms in a social stress context. A total of 29 adolescents between the ages of 13 and 17 years old (Mage = 15.31; SD = 1.51; 55.2% cisgender girls) participated in the present study. Participants were asked to complete a semi-structured interview; fill out self-report questionnaires regarding social anxiety, stress, depression, and anhedonia; and complete a magnetic resonance imaging scan while playing the Island Getaway task. Ventral striatum (VS) BOLD signal activation estimates were then extracted during discrete phases of the game (e.g., anticipation of social feedback and outcome of social feedback) and statistically compared within-subjects via paired samples t-tests and correlated to social anxiety measures. Additionally, regression analyses assessed the effect of VS activation on anhedonia as well as the associative effect of peer victimization on VS activation and anhedonia. Results revealed that when in the presence of social stress (defined as the potential for negative feedback), socially anxious adolescents demonstrated significantly suppressed VS activation relative to baseline when anticipating feedback. Additionally, results indicated that the degree of reduced VS activation during anticipation was correlated to total changes in anhedonia severity across the task. Lastly, results demonstrated that overt peer victimization is a significant predictor of suppressed VS activation during anticipation of social feedback, but not during social outcomes. Taken together, these results identify potentially novel mechanisms associated with anhedonia and blunted reward processing in socially anxious youth that could be improved via interventions that target positive-valence systems. / Doctor of Philosophy / Socially anxious teens may be at a heightened risk for developing anhedonia – which means that they are showing a significant lack of interest in things they used to find interesting or rewarding. This is problematic, because the presence of anhedonia is associated with not doing as well in therapy and even with higher rates of suicide attempt. One area that may be linked to the development of anhedonia in socially anxious teens is social stress induced disrupted reward processing in certain regions of the brain that generally activate when people anticipate a reward. Despite this, there is very little research on the development of anhedonia is socially anxious teens and even less that focuses on biological and behavioral experiences of reward processing when under social stress. This study examines this potential stress-to-anhedonia pipeline by looking at a key region of the brain, called the ventral striatum, to see if social stress does disrupt reward processing in socially anxious teens, and, if so, if this disrupted reward processing is related to anhedonia. Through evaluating a total of 29 socially anxious teens who underwent a social stress task while completing brain scanning, the present study demonstrated evidence for diminished brain activation in the ventral striatum when anticipating rewards. Additionally, the present study showed that reduced brain activation in the ventral striatum was associated with changes in anhedonia severity. Lastly, results from this study indicated that peer victimization (or bullying) was a significant predictor of diminished brain activation in the ventral striatum. Taken together, these results identify potentially new markers associated with anhedonia and blunted reward processing in socially anxious youth that could be improved via interventions.
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