1,252 research outputs found

    Epileptic focus localization using functional brain connectivity

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    Newborn EEG connectivity analysis using time-frequency signal processing techniques

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    Dynamics and network structure in neuroimaging data

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    Trauma-centred identity and autobiographical memory in posttraumatic stress disorder (PTSD)

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    Posttraumatic stress disorder is a prevalent and disabling disorder that can occur following experience of trauma. Contemporary clinical models of PTSD assert that memories for trauma are poorly elaborated and inadequately integrated into autobiographical memory (AM). Recent work of cognitive psychologists suggests, however, that trauma memories remain highly accessible and form a cognitive reference point for the organisation of autobiographical knowledge, leading to the development of trauma-centred identity. The current study sought to explore further the relationships between PTSD symptoms, the phenomenological properties of AM for trauma, and trauma-centred identity. A community sample of 82 participants (male, n = 24; mean age = 36.10 years, SD = 10.82) was recruited. A within-subjects, correlational design was employed. Participants completed online questionnaires relating to PTSD symptoms, the phenomenological properties of a trauma memory and negative memory, and centrality of event to identity. Participants also provided written narratives of both a trauma and negative event. Differences between traumatic and negative memories, and relationships between trauma memory features and both PTSD and centrality were assessed using computerised textual analysis and self-report measures. Results indicated that trauma memories were significantly less coherent, less detailed, and contained fewer spatial references but more cognitive process terms than negative memories. PTSD symptoms correlated significantly with fragmentation of trauma memories and with use of the present tense in trauma narratives. A sense of reliving when remembering trauma and use of present tense were both significantly associated with centrality of event. Results were thus primarily consistent with contemporary clinical theories of PTSD with certain 3 elements of the centrality position also demonstrated. Findings were discussed in relation to the study’s methodological limitations, including difficulties encountered through LIWC’s lack of consideration of context when counting lexical items. Theoretical implications regarding the measurement of constructs such as fragmentation were outlined. Findings supported current treatment guidelines

    Precis of neuroconstructivism: how the brain constructs cognition

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    Neuroconstructivism: How the Brain Constructs Cognition proposes a unifying framework for the study of cognitive development that brings together (1) constructivism (which views development as the progressive elaboration of increasingly complex structures), (2) cognitive neuroscience (which aims to understand the neural mechanisms underlying behavior), and (3) computational modeling (which proposes formal and explicit specifications of information processing). The guiding principle of our approach is context dependence, within and (in contrast to Marr [1982]) between levels of organization. We propose that three mechanisms guide the emergence of representations: competition, cooperation, and chronotopy; which themselves allow for two central processes: proactivity and progressive specialization. We suggest that the main outcome of development is partial representations, distributed across distinct functional circuits. This framework is derived by examining development at the level of single neurons, brain systems, and whole organisms. We use the terms encellment, embrainment, and embodiment to describe the higher-level contextual influences that act at each of these levels of organization. To illustrate these mechanisms in operation we provide case studies in early visual perception, infant habituation, phonological development, and object representations in infancy. Three further case studies are concerned with interactions between levels of explanation: social development, atypical development and within that, developmental dyslexia. We conclude that cognitive development arises from a dynamic, contextual change in embodied neural structures leading to partial representations across multiple brain regions and timescales, in response to proactively specified physical and social environment

    Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 187

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    This supplement to Aerospace Medicine and Biology lists 247 reports, articles and other documents announced during November 1978 in Scientific and Technical Aerospace Reports (STAR) or in International Aerospace Abstracts (IAA). In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which man is subjected during and following simulated or actual flight in the earth's atmosphere or in interplanetary space. References describing similar effects of biological organisms of lower order are also included. Emphasis is placed on applied research, but reference to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the bibliography consists of a bibliographic citation accompanied in most cases by an abstract

    Multivariate assessment of linear and non-linear causal coupling pathways within the central-autonomic-network in patients suffering from schizophrenia

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    Im Bereich der Zeitreihenanalyse richtet sich das Interesse zunehmend darauf, wie Einblicke in die Interaktions- und Regulationsprozesse von pathophysiologischen- und physiologischen Zuständen erlangt werden können. Neuste Fortschritte in der nichtlinearen Dynamik, der Informationstheorie und der Netzwerktheorie liefern dabei fundiertes Wissen über Kopplungswege innerhalb (patho)physiologischer (Sub)Systeme. Kopplungsanalysen zielen darauf ab, ein besseres Verständnis dafür zu erlangen, wie die verschiedenen integrierten regulatorischen (Sub)Systeme mit ihren komplexen Strukturen und Regulationsmechanismen das globale Verhalten und die unterschiedlichen physiologischen Funktionen auf der Ebene des Organismus beschreiben. Insbesondere die Erfassung und Quantifizierung der Kopplungsstärke und -richtung sind wesentliche Aspekte für ein detaillierteres Verständnis physiologischer Regulationsprozesse. Ziel dieser Arbeit war die Charakterisierung kurzfristiger unmittelbarer zentral-autonomer Kopplungspfade (top-to-bottom und bottom to top) durch die Kopplungsanalysen der Herzfrequenz, des systolischen Blutdrucks, der Atmung und zentraler Aktivität (EEG) bei schizophrenen Patienten und Gesunden. Dafür wurden in dieser Arbeit neue multivariate kausale und nicht-kausale, lineare und nicht-lineare Kopplungsanalyseverfahren (HRJSD, mHRJSD, NSTPDC) entwickelt, die in der Lage sind, die Kopplungsstärke und -richtung, sowie deterministische regulatorische Kopplungsmuster innerhalb des zentralen-autonomen Netzwerks zu quantifizieren und zu klassifizieren. Diese Kopplungsanalyseverfahren haben ihre eigenen Besonderheiten, die sie einzigartig machen, auch im Vergleich zu etablierten Kopplungsverfahren. Sie erweitern das Spektrum neuartiger Kopplungsansätze für die Biosignalanalyse und tragen auf ihre Weise zur Gewinnung detaillierter Informationen und damit zu einer verbesserten Diagnostik/Therapie bei. Die Hauptergebnisse dieser Arbeit zeigen signifikant schwächere nichtlineare zentral-kardiovaskuläre und zentral-kardiorespiratorische Kopplungswege und einen signifikant stärkeren linearen zentralen Informationsfluss in Richtung des Herzkreislaufsystems auf, sowie einen signifikant stärkeren linearen respiratorischen Informationsfluss in Richtung des zentralen Nervensystems in der Schizophrenie im Vergleich zu Gesunden. Die detaillierten Erkenntnisse darüber, wie die verschiedenen zentral-autonomen Netzwerke mit paranoider Schizophrenie assoziiert sind, können zu einem besseren Verständnis darüber führen, wie zentrale Aktivierung und autonome Reaktionen und/oder Aktivierung in physiologischen Netzwerken unter pathophysiologischen Bedingungen zusammenhängen.In the field of time series analysis, increasing interest focuses on insights gained how the coupling pathways of regulatory mechanisms work in healthy and ill states. Recent advances in non-linear dynamics, information theory and network theory lead to a new sophisticated body of knowledge about coupling pathways within (patho)physiological (sub)systems. Coupling analyses aim to provide a better understanding of how the different integrated physiological (sub)systems, with their complex structures and regulatory mechanisms, describe the global behaviour and distinct physiological functions at the organism level. In particular, the detection and quantification of the coupling strength and direction are important aspects for a more detailed understanding of physiological regulatory processes. This thesis aimed to characterize short-term instantaneous central-autonomic-network coupling pathways (top-to-bottom and bottom to top) by analysing the coupling of heart rate, systolic blood pressure, respiration and central activity (EEG) in schizophrenic patients and healthy participants. Therefore, new multivariate causal and non-causal linear and non-linear coupling approaches (HRJSD, mHRJSD, NSTPDC) that are able to determine the coupling strength and direction were developed. Whereby, the HRJSD and mHRJSD approaches allow the quantification and classification of deterministic regulatory coupling patterns within and between the cardiovascular- the cardiorespiratory system and the central-autonomic-network were developed. These coupling approaches have their own unique features, even as compared to well-established coupling approaches. They expand the spectrum of novel coupling approaches for biosignal analysis and thus contribute in their own way to detailed information obtained, and thereby contribute to improved diagnostics/therapy. The main findings of this thesis revealed significantly weaker non-linear central-cardiovascular and central-cardiorespiratory coupling pathways, and significantly stronger linear central information flow in the direction of the cardiac- and vascular system, and a significantly stronger linear respiratory information transfer towards the central nervous system in schizophrenia in comparison to healthy participants. This thesis provides an enhanced understanding of the interrelationship of central and autonomic regulatory mechanisms in schizophrenia. The detailed findings on how variously-pronounced, central-autonomic-network pathways are associated with paranoid schizophrenia may enable a better understanding on how central activation and autonomic responses and/or activation are connected in physiology networks under pathophysiological conditions

    Paraphrase or parasite? The Semiotic Stories of Translation

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    Translation, for Saussure, assumed the codified rule of language respecting the difference between synchronic and diachronic linguistics. Translation may be regarded as a theoretical possibility, though impossible for the creative speech of language speakers. Peirce’s logical semiotics reasoned the linguistic-and-cultural (linguïcultural) interpretants of received signs. Semiotranslation is a semiotic game to change the symbiosis of two languages into one language. Identified with both Saussure and Peirce, Jakobson’s intralingual, interlingual, and intersemiotic forms of translation propose rewording, translation proper, and transmutation. Peirce’s semiosis creates simple and complex symbols but navigates between translation, semiotranslation, and transduction. Translation derives from the para-functions of replicas in “paraphrase” and “parasite” to signify the multiplicity of ideas and trends in biotranslation. The source text can be re-organized into the iconic activity of Saussurean paraphrase; or the target text can be indexically recontextualized in the parasitical evolution of Peirce’s instinct and facts of life applied to arts — neither approaching pure science.publishedVersio
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