14,746 research outputs found

    Conflicting Views on Fair Siting Processes: Evidence from Austria and the U.S.

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    The authors maintain that, by granting legitimacy to different notions of fairness and building on common values such as responsibility, it is possible to design siting procedures that promote social cohesion, trust and a sense of fair play

    Neural signals encoding shifts in beliefs

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    Dopamine is implicated in a diverse range of cognitive functions including cognitive flexibility, task switching, signalling novel or unexpected stimuli as well as advance information. There is also longstanding line of thought that links dopamine with belief formation and, crucially, aberrant belief formation in psychosis. Integrating these strands of evidence would suggest that dopamine plays a central role in belief updating and more specifically in encoding of meaningful information content in observations. The precise nature of this relationship has remained unclear. To directly address this question we developed a paradigm that allowed us to decompose two distinct types of information content, information-theoretic surprise that reflects the unexpectedness of an observation, and epistemic value that induces shifts in beliefs or, more formally, Bayesian surprise. Using functional magnetic-resonance imaging in humans we show that dopamine-rich midbrain regions encode shifts in beliefs whereas surprise is encoded in prefrontal regions, including the pre-supplementary motor area and dorsal cingulate cortex. By linking putative dopaminergic activity to belief updating these data provide a link to false belief formation that characterises hyperdopaminergic states associated with idiopathic and drug induced psychosis

    Perceived Cognitive Changes with Chemotherapy for Breast Cancer: A Pilot Study

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    Purpose The purpose of this study was to determine perceived cognitive functioning, fatigue, depression and general well-being among women before and after the initiation of chemotherapy for breast cancer compared to a sample of healthy women. Method This descriptive, repeated measures study compared women receiving chemotherapy and healthy women. Women completed measures of quality of life, fatigue, cognitive changes and depression. Results Before chemotherapy, women with cancer reported more fatigue and depression than healthy women. After chemotherapy, women with cancer reported decreased cognitive functioning accompanied by more fatigue and depressive symptoms than healthy women. Conclusion This study is one of the first to use multiple symptom measures before and after starting chemotherapy. Understanding cognitive changes and related symptoms that occur before and during chemotherapy for breast cancer is the first step toward helping women cope with changes that occur with breast cancer treatment

    The Dopaminergic Midbrain Encodes the Expected Certainty about Desired Outcomes

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    Dopamine plays a key role in learning; however, its exact function in decision making and choice remains unclear. Recently, we proposed a generic model based on active (Bayesian) inference wherein dopamine encodes the precision of beliefs about optimal policies. Put simply, dopamine discharges reflect the confidence that a chosen policy will lead to desired outcomes. We designed a novel task to test this hypothesis, where subjects played a "limited offer" game in a functional magnetic resonance imaging experiment. Subjects had to decide how long to wait for a high offer before accepting a low offer, with the risk of losing everything if they waited too long. Bayesian model comparison showed that behavior strongly supported active inference, based on surprise minimization, over classical utility maximization schemes. Furthermore, midbrain activity, encompassing dopamine projection neurons, was accurately predicted by trial-by-trial variations in model-based estimates of precision. Our findings demonstrate that human subjects infer both optimal policies and the precision of those inferences, and thus support the notion that humans perform hierarchical probabilistic Bayesian inference. In other words, subjects have to infer both what they should do as well as how confident they are in their choices, where confidence may be encoded by dopaminergic firing

    The distribution and feeding ecology of gulls on the tidal reaches of polluted rivers in North East England

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    The study was concerned with investigating the manner in which six species of gulls utilized a tidal river habitat and with studying the factors that influence their distribution in this habitat. The study areas were on the tidal reaches of the Rivers Tyne, Wear and Tees. Regular censuses were taken of the numbers of gulls of each species in the study areas and their distribution was studied in relation to a number of factors which included the amount of sewage entering the section, the amount of mud exposed along the banks at low tide, the degree of urbanization along the banks of the sections, and the width of the river. The various species were found to be affected differently by the factors studied. From the census data observations were made on the seasonal variations in the number of gulls along the rivers. An investigation was made of the feeding behaviour and food preferences of the gulls frequenting the rivers. The study indicated that the species concerned had specialized in their food preferences and feeding methods so that the food sources present were used by one or more species. Detailed work was done on the effects of tide and time of day on the feeding patterns of Common and Black-headed Gulls and some detailed studies were made on the distribution of gulls feeding on the rivers in relation to sewage outfalls. Observations were also made on the preferred resting places of the gulls along the rivers. The relative importance of sewage outfalls as feeding sites gives a means of predicting the effects of proposed reduction of sewage pollution of the river. Such sections are likely to affect the Black-headed, Herring and Greater Black-backed Gulls to the greatest extent and the Kittiwake least

    The use of the Communication Checklist - Adult (CC-A) for assessing the communication abilities of individuals post traumatic brain injury

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    Background and aims: Standardised and non-standardised assessments are used in speech pathology to evaluate an individual’s communication abilities post traumatic brain injury (TBI; e.g. Turkstra et al., 2005b). However, valid, reliable and norm-referenced standardised assessments that examine functional communication abilities of individuals post TBI outside of the clinical environment are limited. This study sought to investigate the validity of the Communication Checklist - Adults (CC-A; Whitehouse & Bishop, 2009), a caregiver questionnaire that assesses the communication abilities of individuals post TBI. Method: The project recruited 14 participants post TBI with varying communicative impairment severities. Each participant completed a routine communication assessment (RCA) which involved administration of a range of assessments. These were 1) the Communication Activities of Daily Living - Second Edition - (CADL-2; Holland, Frattali, & Fromm, 1999), a clinician-administered language assessment that generates percentile scores, with a higher percentile indicating better performance; 2) participation in a conversation which was analysed using Prutting and Kirchner’s pragmatic protocol (PKPP; Prutting & Kirchner, 1987); 3) collection of a monologic discourse sample through two single picture descriptions and description of two picture sequences. Discourse samples were transcribed and a composite of linguistic and pragmatic abilities were generated using measures derived from the Systematic Analysis of Language Transcription (SALT; Miller & Iglesias, 2008), where higher totals on test scoring indicated greater language difficulties. A caregiver or relative of the individual with TBI was also asked to complete the CC-A regarding the individual’s communication ability. The CC-A generated z scores that provided an overall measure of language abilities, as well as subscale measures of linguistic (Language Structure subscale) and pragmatic (Pragmatic Skills subscale and Social Engagement subscale) competence. Lower scores indicated greater difficulties. Results: Pearson’s correlation coefficients identified a strong positive correlation between the CC-A Overall z-scores and the CADL-2 percentile scores (r(14) = .70, p = .01). There were also statistically significant negative correlations between the CC-A Language Structure z-scores and the SALT Linguistic Composite totals, r(14) = -.65, p = .01, as well as between the CC-A Pragmatic Skills z-scores and SALT Pragmatic Composite totals, r(14) = -.53, p = .05. There were statistical trends for an association between CC-A Social Engagement z-scores and the PKPP ratings (r(14) = .48, p = .08) and between Social Engagement z-scores and the SALT Pragmatic Composite totals (r(14) = -.40, p = .15), but these correlations did not achieve statistical significance. Discussion: The results of this study provide preliminary evidence that the CC-A is a valid measure of the communication difficulties experienced by individuals with TBI. Future studies that assess a larger number of patients with a greater range of difficulties, will build on the findings presented here
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