204 research outputs found

    Social learning and information sharing: an evolutionary simulation model of foraging in Norway rats

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    Social learning is distinguished from innate behaviour and individual learning as a behavioural strategy. We investigate simple mechanisms for social learning in an evolutionary simulation of food-preference copying in Norway rats. These animals learn preferences by interacting with conspecifics, but, unexpectedly, they fail to learn aversions after interacting with a poisoned demonstrator. They also follow each other for food sites. Simulation results show that failure to discriminate between sick and healthy demonstrators may be due to food toxicity in foraging environments. A seemingly complex instance of social information transmission is explained through the action of simple behaviours in an appropriately structured environment

    Environments for sonic ecologies

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    This paper outlines a current lack of consideration for the environmental context of Evolutionary Algorithms used for the generation of music. We attempt to readdress this balance by outlining the benefits of developing strong coupling strategies between agent and en- vironment. It goes on to discuss the relationship between artistic process and the viewer and suggests a placement of the viewer and agent in a shared environmental context to facilitate understanding of the artistic process and a feeling of participation in the work. The paper then goes on to outline the installation ‘Excuse Me and how it attempts to achieve a level of Sonic Ecology through the use of a shared environmental context

    Differing effects when using phenylephrine and norepinephrine to augment cerebral blood flow after traumatic brain injury in the immature brain

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    Low cerebral blood flow (CBF) states have been demonstrated in children early after traumatic brain injury (TBI), and have been correlated with poorer outcomes. Cerebral perfusion pressure (CPP) support following severe TBI is commonly implemented to correct cerebral hypoperfusion, but the efficacy of various vasopressors has not been determined. Sixteen 4-week-old female swine underwent nonimpact inertial brain injury in the sagittal plane. Intraparenchymal monitors were placed to measure intracranial pressure (ICP), CBF, brain tissue oxygen tension (PbtO(2)), and cerebral microdialysis 30 min to 6 h post-injury. One hour after injury, animals were randomized to receive either phenylephrine (PE) or norepinephrine (NE) infusions titrated to a CPP >70 mm Hg for 5 h. Animals were euthanized 6 h post-TBI, and brains were fixed and stained to assess regions of cell and axonal injury. After initiation of CPP augmentation with NE or PE infusions, there were no differences in ICP between the groups or over time. Animals receiving NE had higher PbtO(2) than those receiving PE (29.6±10.2 vs. 19.6±6.4 torr at 6 h post-injury, p<0.05). CBF increased similarly in both the NE and PE groups. CPP support with PE resulted in a greater reduction in metabolic crisis than with NE (lactate/pyruvate ratio 16.7±2.4 vs. 42.7±10.2 at 6 h post-injury, p<0.05). Augmentation of CPP to 70 mm Hg with PE resulted in significantly smaller cell injury volumes at 6 h post-injury than CPP support with NE (0.4% vs. 1.4%, p<0.05). Despite similar increases in CBF, CPP support with NE resulted in greater brain tissue oxygenation and hypoxic-ischemic injury than CPP support with PE. Future clinical studies comparing the effectiveness of various vasopressors for CPP support are warranted

    Mind, rationality, and cognition: an interdisciplinary debate

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    This article features an interdisciplinary debate and dialogue about the nature of mind, perception, and rationality. Scholars from a range of disciplines—cognitive science, applied and experimental psychology, behavioral economics, and biology—offer critiques and commentaries of a target article by Felin, Koenderink, and Krueger (2017): “Rationality, Perception, and the All-Seeing Eye,” Psychonomic Bulletin & Review. The commentaries raise a number of criticisms and issues concerning rationality and the all-seeing-eye argument, including the nature of judgment and reasoning, biases versus heuristics, organism–environment relations, perception and situational construal, equilibrium analysis in economics, efficient markets, and the nature of empirical observation and the scientific method. The debated topics have far-reaching consequences for the rationality literature specifically, as well as for the cognitive, psychological, and economic sciences more broadly. The commentaries are followed by a response from the authors of the target article. Their response is organized around three central issues: (1) the problem of cues; (2) what is the question?; and (3) equilibria, $500 bills, and the axioms of rationality

    Structural, item, and test generalizability of the psychopathology checklist - revised to offenders with intellectual disabilities

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    The Psychopathy Checklist–Revised (PCL-R) is the most widely used measure of psychopathy in forensic clinical practice, but the generalizability of the measure to offenders with intellectual disabilities (ID) has not been clearly established. This study examined the structural equivalence and scalar equivalence of the PCL-R in a sample of 185 male offenders with ID in forensic mental health settings, as compared with a sample of 1,212 male prisoners without ID. Three models of the PCL-R’s factor structure were evaluated with confirmatory factor analysis. The 3-factor hierarchical model of psychopathy was found to be a good fit to the ID PCL-R data, whereas neither the 4-factor model nor the traditional 2-factor model fitted. There were no cross-group differences in the factor structure, providing evidence of structural equivalence. However, item response theory analyses indicated metric differences in the ratings of psychopathy symptoms between the ID group and the comparison prisoner group. This finding has potential implications for the interpretation of PCL-R scores obtained with people with ID in forensic psychiatric settings

    Consumer understanding of nutrition and health claims: sources of evidence

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    Provided that they are scientifically substantiated, nutrition and health (NH) claims linked to food products can help consumers make well-informed food choices. The new European legislation on NH claims made on foods entered into force on 19 January 2007. The law sets out conditions for their use, establishes a system for their scientific evaluation, and will create European lists of authorised claims. An important aspect of this proposed legislation is that it states, in article 5.2, `the use of nutrition and health claims shall only be permitted if the average consumer can be expected to understand the beneficial effects expressed in the claimÂż. The present review examines consumer understanding of NH claims from a consumer science perspective. It focuses on the type of data and information that could be needed to provide evidence that the average consumer adequately understands a particular NH claim. After exploring several different methodologies, it proposes a case-specific approach using a stepwise procedure for assessing consumer understanding of a NH claim. Key Words: Nutrition and health claims; Consumer understanding; Claim methodology; Legislatio

    Vague heuristics

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    Even when they are defined with precision, one can often read and hear judgments about the vagueness of heuristics in debates about heuristic reasoning. This opinion is not just frequent but also quite reasonable. In fact, during the 1990s, there was a certain controversy concerning this topic that confronted two of the leading groups in the field of heuristic reasoning research, each of whom held very different perspectives. In the present text, we will focus on two of the papers published in Psychological Review, wherein the arguments of each of these groups were presented:

    Re-evaluation and extension of the Marine Isotope Stage 5 tephrostratigraphy of the Faroe Islands region: The cryptotephra record

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    PMA, SMD, WENA and NJGP are supported by NERC through the SMART project (NE/F020600/1, NE/F02116X/1, NE/F021445/1). The research leading to the results for the MIS 4 and 5a tephra horizons has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) / ERC grant agreement n° [259253]. PMA, SMD and NJGP acknowledge the support of the Climate Change Consortium of Wales (C3W). JB is funded by the Research Council of Norway through the INTERACT project (project no. 221999).Abstract Previous studies of marine sequences from the Faroe Islands region have identified a series of coarse-grained tephra horizons deposited during Marine Isotope Stage (MIS) 5. Here we reassess the MIS 5 tephrostratigraphy of the Faroe Islands region and focus on the cryptotephra deposits preserved within the fine-grained fraction of marine core LINK 16. We also extend the record to encompass the late MIS 6 and early MIS 4 periods. A density separation technique, commonly used for tephra investigations in lacustrine settings but rarely applied to marine sediments, is utilised to explore the fine-grained material and EPMA and LA-ICP-MS are employed to determine the major and trace element composition of individual tephra shards. In total, 3 basaltic and 3 rhyolitic Icelandic cryptotephra deposits with homogeneous geochemical compositions are identified — all of which have the potential to act as isochronous tie-lines. Geochemical results highlight that the GrĂ­msvötn volcanic system of Iceland is the predominant source of the basaltic horizons and the Öraefajökull or Torfajökull systems are the likely sources of the rhyolitic deposits. Three of the horizons have been previously recognised in Faroe Islands region marine sequences, with two of these deposits traceable into a Norwegian Sea sequence. An early MIS 4 rhyolitic horizon is the most widespread deposit as it can be traced into the Norwegian Sea and to the south into a record from the Rockall Trough. Basaltic and rhyolitic horizons deposited during late MIS 6 have not been recognised in other sequences and represent new additions to the regional tephrostratigraphy.Publisher PDFPeer reviewe
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