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Quantum Cohomology Rings of Grassmannians and Total PositivityKonstanze Rietsch, rietsch@dpmms.cam.ac.uk 31 July 2000 (has links)
No description available.
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Extrinsic and Intrinsic Factors Influencing the Positive Memory Bias in AgingAck Baraly, Kylee Tamera 27 January 2020 (has links)
Emotional experiences are more likely to be remembered than more neutral, mundane ones. In young adults, negative information may be particularly memorable. Yet, an interesting change seems to happen in aging: As adults grow older, they may start remembering positive information more often than negative information. This positive memory bias in aging is commonly observed and is often explained in terms of changing time perspectives and motivation across the lifespan (i.e., Socioemotional Selectivity Theory; Carstensen, Isaacowitz, & Charles, 1999). However, few studies have considered the basic interactions between memory and emotion that could influence this positivity bias. In this thesis, I examine whether certain factors partially independent of aging (i.e., semantic relatedness and distinctiveness, Study 1; mood, Studies 2-4), might influence the presence and magnitude of the positivity bias in memory. In Study 1, I explore the cognitive mechanisms required to produce the positivity bias and apply what is learned in this paper to investigate, in Studies 2-4, whether differences in mood could explain why the positivity bias occurs. In all studies, memory is measured using immediate free recall of positive, negative, and neutral pictures. In Study 1, I manipulate item interrelatedness (i.e., the extent of relatedness among pictures of a same category) and relative distinctiveness (i.e., the processing of a picture category at the same time as or in isolation from the others) to show that older adults’ emotional memory can be entirely explained by these two factors. The distinctive processing of positive pictures relative to other pictures is necessary for producing a positivity bias in older adults, which completely disappears when the distinctive processing of positive pictures is removed. Therefore, in subsequent studies I encourage the distinctive processing of items to increase the likelihood of observing a positivity bias and its possible interaction with mood. In Study 2, I test whether differences in mood predict differences in emotional memory bias in young and older adults using a video mood induction technique validated in a separate pilot study. In Studies 3 and 4, I further test the effect of mood on the positivity bias beyond any age-specific factors, by examining young adults only. This serves to reduce the likelihood of confounds that might exist between age groups (i.e., related to neurocognitive changes or decline), in order to study the true effects of mood on the positivity bias. In Study 3, I use a written priming task to experimentally manipulate mood and time perspective in young adults. In Study 4, I compare differences in naturally occurring moods and emotional memory in two separate young adult samples: university students and non-students. The experimental mood manipulations have minimal influence on the presence of a negativity bias in young adults (Studies 2 and 3), and influence to a small extent the memory advantage of positive over neutral material in older adults (Study 2). Non-student young adults show a similar preferential memory for positive material that is different from what is observed in university students, but this is not easily attributed to differences in mood (Study 4). In light of these results, I argue that the positivity effect in aging memory reflects a temporary contextual advantage for positive information that is not permanent or irreversible. Rather, it seems to depend in varying degrees on the context of study (i.e., relatedness and distinctiveness), mood, and the young-adult reference group. This has implications for how future research defines and studies the positivity effect in aging.
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Mechanisms of the Aging-Related Positivity Effect in Memory and AttentionTomaszczyk, Jennifer Christina January 2012 (has links)
According to the Socioemotional Selectivity Theory (SST), the normal aging process is associated with a greater emphasis on self-regulation of emotional states, and this fosters a bias in cognitive processing for information that is positively valenced (e.g., pleasant images and autobiographical events, happy faces), such that older adults have better memory for, and pay greater attention to, positive relative to negative valenced information (a ???positivity effect???). Two hypotheses have recently emerged which differ in the cognitive mechanism proposed to account for the emergence of aging-related positivity effects. The first, termed the ???cognitive control??? hypothesis, suggests that positivity effects arise from older adults' directed application of cognitive efforts to preferentially process positive information, essentially a top-down explanation. The second is a bottom-up hypothesis, suggesting that positive information is relatively easier (more fluent) for older adults to detect and process, compared to negative information, due to changes in amygdala reactivity to negative stimuli, and is termed the "processing fluency" hypothesis. To evaluate these hypotheses, I conducted a suite of memory and attention experiments and compared performance of younger and older adults. I used five different tasks (three different memory tasks, and two different attention tasks) which varied with respect to the degree to which each allowed for the use of cognitive control, and was reflective in nature, or emphasized fluency (i.e., speed of processing and output). In Experiments 1 and 2, I examined the effect of age on two different types of memory task that differed with respect to the degree to which participants must rely on cognitive control/reflective processing or processing fluency to successfully complete the task. Clear positivity effects were found on the task that was reflective in nature (autobiographical memory task) but not on the task that relied more heavily on fluency (phonemic fluency task). In Experiment 3, I examined whether older adults strategically select positive information to later remember (i.e., use cognitive control to regulate encoding of positive material), by asking participants to judge the likelihood of remembering positive, negative, and neutral pictures for a later memory test. In line with a strategic bias, older, but not younger, adults showed a positivity effect in terms of the number of pictures selected as particularly memorable, though both age groups showed a positivity effect in picture recall. Within the domain of attention-based tasks, in Experiments 4a and 4b I used a Rapid Serial Visual Presentation (RSVP) paradigm to examine whether older adults were more likely to detect (or have attention captured by) rapidly presented positive, than negative or neutral, pictures compared to younger adults. Given the rapid rate of presentation in this paradigm, it is unlikely that participants would be able to use cognitive control to strategically direct attention to positive stimuli, thus performance was taken to measure fluency-mediated biases for the pictures of different valence. Results showed little evidence for a positivity effect. In Experiments 5a and 5b, again within the domain of attention, I examined whether older adults preferentially oriented attention toward positive, and/or away from negative, relative to neutral stimuli, on a dot probe task in which trial timings were long enough to allow for strategic control. Experiment 5a used faces whereas Experiment 5b used pictures as stimuli, in an effort to determine whether findings could generalize across different types of stimuli. Some evidence of positivity effects were found, as older adults were less biased to attend to negative (angry) faces compared to younger adults. Results across this series of experiments are consistent with the hypothesis that positivity effects in older adults' memory and attention stem from the strategic application of effortful, reflective, cognitive processing, rather than a bottom-up difference in processing fluency.
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Motor expectancy: the modulation of the reward positivity in a reinforcement learning motor taskTrska, Robert 30 August 2018 (has links)
An adage posits that we learn from our mistakes; however, this is not entirely true. According to reinforcement learning theory, we learn when the expectation of our actions differs from outcomes. Here, we examined whether expectancy driven learning lends a role in motor learning. Given the vast amount of overlapping anatomy and circuitry within the brain with respect to reward and motor processes, it is appropriate to examine both motor control and expectancy processes within a singular task. In the current study, participants performed a line drawing task via tablet under conditions of changing expectancies. Participants were provided feedback in a reinforcement-learning manner, as positive (✓) or negative (x) based off their performance. Modulation of expected outcomes were reflected by changes in amplitude of the human event-related potential (ERP), the reward positivity. The reward positivity is thought to reflect phasic dopamine release from the mesolimbic dopaminergic system to the basal ganglia and cingulate cortex. Due to the overlapping circuitry of reward and motor pathways, another human ERP, the bereitschatftspotential (BP), was examined. The BP is implicated in motor planning and execution; however, the late aspect of the BP shares similarity with the contingent negative variability (CNV). Current evidence demonstrates a relationship between expectancy and reward positivity amplitude in a motor learning context, as well as modulation of the BP under difficult task conditions. Behavioural data supports prior literature and may suggest a connection between sensory motor prediction errors working in concert with reward prediction errors. Further evidence supports a frontal-medial evaluation system for motor errors. Additionally, results support prior evidence of motor plans being formed upon target observation and held in memory until motor execution, rather than their formation before movement onset. / Graduate
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The Authenticity of Body Positivity in the Media: A Comparative Analysis of Four American-Owned CompaniesMink, Emma 01 May 2022 (has links)
Marketing strategies are changing how businesses sell their products. The body positivity movement is causing consumers to examine companies to determine if their intentions are authentic. Some of the ways consumers evaluate company authenticity include examining corporate social responsibility reports, types of advertising, or the brand-cause fit between the company and the body positivity movement. The author of this study followed two companies (Dove and Aerie) that are known for body positive advertising messages and two companies (Mattel/Barbie and Victoria Secret) that are known for promoting unrealistic body expectations. The author examined each companies’ mission statement, annual report, and types of media being used to determine whether the companies were doing what they say they are doing. The researchers found that Dove and Aerie demonstrated company values consistent with their body positivity campaigns; however, both had opportunities to increase their emphasis on inclusion and diversity in their advertising campaigns and media presence. Mattel and Victoria’s Secret had inclusive and diverse campaigns and media presence but focused on empowerment of women rather than body positivity. In the final analysis, Aerie had the most consistency between its brand and its body positivity campaigns. Further, the author found that Aerie’s campaigns promoted true body positivity with models of various ethnicities, sizes, disabilities, and illnesses. Aerie has raised the bar for companies joining the body positivity movement by encouraging women to accept the “imperfect” bodies they were born with. This study has academic and industry contributions due to the comparative analyses of the body positivity marketing campaigns of American-owned brands. The results could inform companies of their strengths and areas of opportunity in consumer perceptions of brand authenticity and could provide direction for future studies focused on body positivity marketing.
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The Authenticity of Body Positivity in the Media: A Comparative Analysis of Four American-Owned CompaniesMink, Emma, Atkins, Kelly G. 06 April 2022 (has links)
The Authenticity of Body Positivity in the Media: A Comparative Analysis of Four American-Owned Companies
Emma Mink and Dr. Kelly Atkins, Department of Marketing and Management, College of Business, East Tennessee State University, Johnson City, TN.
Marketing strategies are changing how businesses sell their products. The body positivity movement is causing consumers to examine companies to determine if their intentions are authentic. Some of the ways consumers evaluate company authenticity include examining corporate social responsibility reports, types of advertising, or the brand-cause fit between the company and the body positivity movement. The authors of this study followed two companies (Dove and Aerie) that are known for body positive advertising messages and two companies (Mattel/Barbie and Victoria Secret) that are known for promoting unrealistic body expectations. The authors examined each companies’ mission statement, annual report, and types of media being used in order to determine whether the companies were doing what they say they are doing. The researchers found that Dove and Aerie demonstrated company values consistent with their body positivity campaigns; however, both had opportunities to increase their emphasis on inclusion and diversity in their advertising campaigns and media presence. Mattel and Victoria’s Secret had inclusive and diverse campaigns and media presence but focused on empowerment of women rather than body positivity. In the final analysis, Aerie had the most consistency between its brand and its body positivity campaigns. Further, the authors found that Aerie’s campaigns promoted true body positivity with models of various ethnicities, sizes, disabilities, and illnesses. Aerie has raised the bar for companies joining the body positivity movement by encouraging women to accept the “imperfect” bodies they were born with. This study has academic and industry contributions due to the comparative analyses of the body positivity marketing campaigns of American-owned brands. The results could inform companies of their strengths and areas of opportunity in consumer perceptions of brand authenticity and could provide direction for future studies focused on body positivity marketing.
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Hyponormality and Positivity of Toeplitz operators via the Berezin transformSubedi, Krishna, Subedi January 2018 (has links)
No description available.
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The Positivity-Cues-Familiarity Effect and Initial Stimulus ValenceHousley, Meghan K. 27 July 2007 (has links)
No description available.
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Father Involvement in Intact Families and StepfamiliesGlover, Marshaun Benjamin 16 August 2007 (has links)
Father involvement was examined multidimensionally using fathers' and children's reports. A total of 61 fathers and 143 children (intact families and stepfather families) from the Avon Brothers and Sisters Study (ABSS) participated in the current study. Measures of father involvement including engagement in shared activity, monitoring, positivity, and negativity were completed by fathers and children. Agreement between father and child reports of involvement was assessed, involvement was compared between biological fathers and stepfathers, and involvement was predicted statistically using father and child factors (e.g., age, gender). There were modest significant associations between fathers' and children's reports of monitoring of positive events, and father-child positivity. Compared to biological fathers, stepfathers did less monitoring of positive events, and were less positive towards their children. Biological relatedness was a significant predictor of monitoring positive events, monitoring negative events, and positivity. Consistent with previous theoretical and empirical accounts, this study demonstrated that being biologically related to your child influences the level of involvement in fathers. / Master of Science
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Age effects on auditory sensory memory: a cognitive neuroscience perspectiveCooper, Rowena January 2009 (has links)
Research Doctorate - Doctor of Philosophy / It is well established that there are changes in cognition and in peripheral sensory mechanisms that occur with age. However, there is much less known about the cause of either change or indeed the relationship between age-related change in sensory processing and age-associated cognitive decline. Understanding these mechanisms could improve our capacity to devise strategies which could assist older adults in aging successfully. In this thesis, I aim to bridge a gap in our knowledge concerning the relationship between age-related change in sensory processing and age-associated cognitive decline by studying the effect of age on what can be considered an intermediary process, sensory memory (in the auditory modality). I continue this line of research by examining the relationship between auditory sensory memory and other types of memory for auditory information in young and older adults. To address these goals, I adopted a cognitive neuroscience approach, relating electrophysiological data to data derived from behavioural memory assessments. In the following thesis, I present a literature review, four studies, and a general discussion of results. Several waveforms of the auditory event-related potential (ERP), including N1, P2, repetition positivity (RP), and mismatch negativity (MMN) were studied. More specifically, in study 1, we looked at the effect of age on N1 and P2 amplitude. In study 2, we examined the conditions eliciting two repetition effects, RP and the MMN memory trace effect, in the auditory ERP of young adults. Studies 3 and 4 concerned the effect of age on RP and the relationship between RP and implicit memory for contextual information as well as explicit memory for auditory information. We concluded that i) age affects auditory sensory memory, ii) the potential relationship between auditory sensory memory and implicit memory for auditory information requires re-investigation, and iii) there is a relationship between auditory sensory memory and explicit memory for auditory information that is altered with age. That is, we concluded that RP occurring in the N1/P2 and MMN latency period indicates memory trace formation and that age affects RP amplitude (restricted to an anterior RP generator). In addition, we showed that RP may be related to implicit memory (priming) in both young and older adults. Across two studies, we found a positive correlation between the response to repetition in the ERP (due to RP activity) and explicit auditory verbal memory in young adults but a negative correlation in older adults. Therefore, although age-related change in RP could reflect the capacity of older adults to encode the context of auditory stimulation, this is potentially due to compensatory activity. We argue it is possible that implicit memory changes with age as a result of age-related change in explicit episodic memory. As a result of well established changes that occur in episodic memory with age, older adults may begin to rely on implicit memory as a source of memory more so than young adults. Our data shows that the implicit memory system may, as a result, favour content over contextual information. An important theme outlined in the discussion of results involves the idea that age-related changes in cognition that are commonly interpreted as cognitive deficits may in fact be beneficial in certain circumstances. We review our results in relation to cognitive theories of aging and find that several theories are applicable to the data, including the frontal hypothesis (incorporating the inhibitory deficit hypothesis), the information degradation hypothesis, and the speed of processing hypothesis. Future research in this area could focus on exploring whether top-down or bottom-up or influences primarily contribute to the age effect on auditory sensory memory and RP, as well as evaluating our hypothesis that the age-related change in RP may be beneficial for explicit item memory but detrimental for implicit contextual memory in older adults (i.e. compensatory mechanisms). While the studies presented in this thesis have provided the foundations guiding our understanding of these issues, researchers in the field of cognitive neuroscience are well equipped to resolve such questions in the future.
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