209 research outputs found

    In search of ontological emergence: diachronic, but non-supervenient

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    Most philosophical accounts of emergence are based on supervenience, with supervenience being an ontologically synchronic relation of determination. This conception of emergence as a relation of supervenience, I will argue, is unable to make sense of the kinds of emergence that are widespread in self-organizing and nonlinear dynamical systems, including distributed cognitive systems. In these dynamical systems, an emergent property is ontological (i.e., the causal capacities of P, where P is an emergent feature, are not reducible to causal capacities of the parts, and may exert a top-down causal influence on the parts of the system) and diachronic (i.e., the relata of emergence are temporally extended, and P emerges as a result of some dynamical lower-level processes that unfold in real time)

    Infanticide in Chimpanzees: Taphonomic Case Studies from Gombe

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    Objectives We present a study of skeletal damage to four chimpanzee (Pan troglodytes) infanticide victims from Gombe National Park, Tanzania. Skeletal analysis may provide insight into the adaptive significance of infanticide by examining whether nutritional benefits sufficiently explain infanticidal behavior. The nutritional hypothesis would be supported if bone survivorship rates and skeletal damage patterns are comparable to those of monkey prey. If not, other explanations, such as the resource competition hypothesis, should be considered. Methods Taphonomic assessment of two chimpanzee infants included description of breakage and surface modification, data on MNE, %MNE, and bone survivorship. Two additional infants were assessed qualitatively. The data were compared to published information on monkey prey. We also undertook a review of published infanticide cases. Results The cases were intercommunity infanticides (one male and three female infants) committed by males. Attackers partially consumed two of the victims. Damage to all four infants included puncture marks and compression fractures to the cranium, crenulated breaks to long bones, and incipient fractures on ribs. Compared to monkey prey, the chimpanzee infants had an abundance of vertebrae and hand/foot bones. Conclusions The cases described here suggest that chimpanzees may not always completely consume infanticide victims, while reports on chimpanzee predation indicated that complete consumption of monkey prey usually occurred. Infanticidal chimpanzees undoubtedly gain nutritional benefits when they consume dead infants, but this benefit may not sufficiently explain infanticide in this species. Continued study of infanticidal and hunting behavior, including skeletal analysis, is likely to be of interest

    A tale of two densities: Active inference is enactive inference

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    The aim of this paper is to clarify how best to interpret some of the central constructs that underwrite the free-energy principle (FEP) – and its corollary, active inference – in theoretical neuroscience and biology: namely, the role that generative models and variational densities play in this theory. We argue that these constructs have been systematically misrepresented in the literature; because of the conflation between the FEP and active inference, on the one hand, and distinct (albeit closely related) Bayesian formulations, centred on the brain – variously known as predictive processing, predictive coding, or the prediction error minimisation framework. More specifically, we examine two contrasting interpretations of these models: a structural representationalist interpretation and an enactive interpretation. We argue that the structural representationalist interpretation of generative and recognition models does not do justice to the role that these constructs play in active inference under the FEP. We propose an enactive interpretation of active inference – what might be called enactive inference. In active inference under the FEP, the generative and recognition models are best cast as realising inference and control – the self-organising, belief-guided selection of action policies – and do not have the properties ascribed by structural representationalists

    Photon Conserving Radiative Transfer around Point Sources in multi-dimensional Numerical Cosmology

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    Many questions in physical cosmology regarding the thermal and ionization history of the intergalactic medium are now successfully studied with the help of cosmological hydrodynamical simulations. Here we present a numerical method that solves the radiative transfer around point sources within a three dimensional cartesian grid. The method is energy conserving independently of resolution: this ensures the correct propagation speeds of ionization fronts. We describe the details of the algorithm, and compute as first numerical application the ionized region surrounding a mini-quasar in a cosmological density field at z=7.Comment: 5 pages, 4 figures, submitted to ApJ

    Multiscale Integration: Beyond Internalism and Externalism

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    We present a multiscale integrationist interpretation on the boundaries of cognitive systems, using the Markov blanket formalism of the variational free energy principle (FEP). This interpretation is intended as a corrective for the philosophical debate over internalist and externalist interpretations of cognitive boundaries; we stake out a compromise position. We first survey key principles of new radical (extended, enactive, embodied) views of cognition. We then describe an internalist interpretation premised on the Markov blanket formalism. Having reviewed these accounts, we develop our positive multiscale account. We argue that the statistical seclusion of internal from external states of the system – entailed by the existence of a Markov boundary – can coexist happily with the multiscale integration of the system through its dynamics. Our approach does not privilege any given boundary (whether it be that of the brain, body, or world), nor does it argue that all boundaries are equally prescient. We argue that the relevant boundaries of cognition depend on the level being characterised and the explanatory interests that guide investigation. We approach the issue of how and where to draw the boundaries of cognitive systems through a multiscale ontology of cognitive systems, which offers a multidisciplinary research heuristic for cognitive science

    Between pebbles and organisms: Weaving autonomy into the Markov blanket

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    The free energy principle (FEP) purports to provide a single principle for the organizational dynamics of living systems, including their cognitive profiles. It states that for a system to maintain non-equilibrium steady-state with its environment it must minimise its free energy. It is said to be entirely scale-free, applying to anything from particles to organisms, and interactive machines, spanning from the abiotic to the biotic. Because the FEP is so general in its application, it is for this reason that one might wonder in what sense this framework captures anything specific to biological characteristics, if details at all. We take steps to correct for this here. We do so by taking up a distinct challenge that the FEP must overcome if it is to be of interest to those working in the biological sciences. We call this the pebble challenge: it states that the FEP cannot capture the organisational principles specific to biology, for its formalisms apply equally well to pebbles. We progress in solving the pebble challenge by articulating how the notion of ‘autonomy as precarious operational closure’ from the enactive literature can be unpacked within the FEP. This enables the FEP to delineate between the abiotic and the biotic; avoiding the pebble challenge that keeps it out of touch with the living systems we encounter in the world and is of interest to the sciences of life and mind

    A tale of two densities: Active inference is enactive inference

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    The aim of this paper is to clarify how best to interpret some of the central constructs that underwrite the free-energy principle (FEP) – and its corollary, active inference – in theoretical neuroscience and biology: namely, the role that generative models and variational densities play in this theory. We argue that these constructs have been systematically misrepresented in the literature; because of the conflation between the FEP and active inference, on the one hand, and distinct (albeit closely related) Bayesian formulations, centred on the brain – variously known as predictive processing, predictive coding, or the prediction error minimisation framework. More specifically, we examine two contrasting interpretations of these models: a structural representationalist interpretation and an enactive interpretation. We argue that the structural representationalist interpretation of generative and recognition models does not do justice to the role that these constructs play in active inference under the FEP. We propose an enactive interpretation of active inference – what might be called enactive inference. In active inference under the FEP, the generative and recognition models are best cast as realising inference and control – the self-organising, belief-guided selection of action policies – and do not have the properties ascribed by structural representationalists

    Multiscale Integration: Beyond Internalism and Externalism

    Get PDF
    We present a multiscale integrationist interpretation on the boundaries of cognitive systems, using the Markov blanket formalism of the variational free energy principle (FEP). This interpretation is intended as a corrective for the philosophical debate over internalist and externalist interpretations of cognitive boundaries; we stake out a compromise position. We first survey key principles of new radical (extended, enactive, embodied) views of cognition. We then describe an internalist interpretation premised on the Markov blanket formalism. Having reviewed these accounts, we develop our positive multiscale account. We argue that the statistical seclusion of internal from external states of the system – entailed by the existence of a Markov boundary – can coexist happily with the multiscale integration of the system through its dynamics. Our approach does not privilege any given boundary (whether it be that of the brain, body, or world), nor does it argue that all boundaries are equally prescient. We argue that the relevant boundaries of cognition depend on the level being characterised and the explanatory interests that guide investigation. We approach the issue of how and where to draw the boundaries of cognitive systems through a multiscale ontology of cognitive systems, which offers a multidisciplinary research heuristic for cognitive science

    Usability of Electronic Health Record-Generated Discharge Summaries: Heuristic Evaluation.

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    BACKGROUND: Obtaining accurate clinical information about recent acute care visits is extremely important for outpatient providers. However, documents used to communicate this information are often difficult to use. This puts patients at risk of adverse events. Elderly patients who are seen by more providers and have more care transitions are especially vulnerable. OBJECTIVE: This study aimed to (1) identify the information about elderly patients\u27 recent acute care visits needed to coordinate their care, (2) use this information to assess discharge summaries, and (3) provide recommendations to help improve the quality of electronic health record (EHR)-generated discharge summaries, thereby increasing patient safety. METHODS: A literature review, clinician interviews, and a survey of outpatient providers were used to identify and categorize data needed to coordinate care for recently discharged elderly patients. Based upon those data, 2 guidelines for creating useful discharge summaries were created. The new guidelines, along with 17 previously developed medical documentation usability heuristics, were applied to assess 4 simulated elderly patient discharge summaries. RESULTS: The initial research effort yielded a list of 29 items that should always be included in elderly patient discharge summaries and a list of 7 helpful, but not always necessary items. Evaluation of 4 deidentified elderly patient discharge summaries revealed that none of the documents contained all 36 necessary items; between 14 and 18 were missing. The documents each had several other issues, and they differed significantly in organization, layout, and formatting. CONCLUSIONS: Variations in content and structure of discharge summaries in the United States make them unnecessarily difficult to use. Standardization would benefit both patients, by lowering the risk of care transition-related adverse events, and outpatient providers, by helping reduce frustration that can contribute to burnout. In the short term, acute care providers can help improve the quality of their discharge summaries by working with EHR vendors to follow recommendations based upon this study. Meanwhile, additional human factors work should determine the most effective way to organize and present information in discharge summaries, to facilitate effective standardization
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