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Integration Theory (integration + theory)
Selected AbstractsLesions of the mammillary body region alter hippocampal movement signals and theta frequency: Implications for path integration modelsHIPPOCAMPUS, Issue 9 2008Patricia E. Sharp Abstract Cells throughout the hippocampal formation are involved in processing spatial information. These same cells also show an influence of locomotor activity, and these movement signals are thought to be critical for the path integration abilities of these cells. Nuclei in the mammillary region provide ascending influences to the hippocampal formation and have been implicated in influencing both hippocampal spatial and theta signals. Here, we report the effects of mammillary lesions on movement-related signals in several hippocampal subregions. We find first, as predicted by earlier work, these lesions cause an approximately 1 Hz reduction in the frequency of theta modulation of cell firing. According to recent theoretical work, this might, in turn, be expected to influence the size of hippocampal place fields. Our data do not confirm this prediction for any of the hippocampal regions examined. Second, we report lesion effects on the relationship between firing rate and running speed for the hippocampal cells. These lesions caused a reduction in both the slope and intercept of rate-by-speed functions for cells in the hippocampus and postsubiculum. Surprisingly, cells in subiculum showed an opposite effect, so that the excitatory influence of locomotion was enhanced. Path integration theories predict that the speed at which path integration occurs is related to the strength of this movement signal. In remarkable accordance with this prediction, we report that the timing of the place cell signals is slowed following mammillary lesions for hippocampal and postsubicular cells, but, in contrast, is speeded up for subicular cells. In fact, the timing for place signals across lesion condition and brain region is predicted by a single linear function which relates timing to the strength of the running speed signal. Thus, these data provide remarkable support for some aspects of current path integration theory, while posing a challenge for other aspects of these same theories. © 2008 Wiley-Liss, Inc. [source] From GATT to the WTO: The Internal Struggle for External Competences in the EUJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 5 2006STIJN BILLIET Despite the rise of ,mixity', the Commission is nonetheless the key European player in the WTO, even regarding issues that are not exclusive EC competences. While established integration theories struggle to explain this phenomenon, this article argues that the external institutional context should be brought into the analysis. [source] Occupational therapy using a sensory integrative approach for children with developmental disabilitiesDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2005Roseann C. Schaaf Abstract This article provides an introduction and overview of sensory integration theory as it is used in occupational therapy practice for children with developmental disabilities. This review of the theoretical tenets of the theory, its historical foundations, and early research provides the reader with a basis for exploring current uses and applications. The key principles of the sensory integrative approach, including concepts such as "the just right challenge" and "the adaptive response" as conceptualized by A. Jean Ayres, the theory's founder, are presented to familiarize the reader with the approach. The state of research in this area is presented, including studies underway to further delineate the subtypes of sensory integrative dysfunction, the neurobiological mechanisms of poor sensory processing, advances in theory development, and the development of a fidelity measure for use in intervention studies. Finally, this article reviews the current state of the evidence to support this approach and suggests that consensual knowledge and empirical research are needed to further elucidate the theory and its utility for a variety of children with developmental disabilities. This is especially critical given the public pressure by parents of children with autism and other developmental disabilities to obtain services and who have anecdotally noted the utility of sensory integration therapy for helping their children function more independently. Key limiting factors to research include lack of funding, paucity of doctorate trained clinicians and researchers in occupational therapy, and the inherent heterogeneity of the population of children affected by sensory integrative dysfunction. A call to action for occupational therapy researchers, funding agencies, and other professions is made to support ongoing efforts and to develop initiatives that will lead to better diagnoses and effective intervention for sensory integrative dysfunction, which will improve the lives of children and their families. © 2005 Wiley-Liss, Inc. MRDD Research Reviews 2005;11:143,148. [source] Flux compactification of M-theory on compact manifolds with Spin(7) holonomy,FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 11-12 2005D. Constantin At the leading order, M-theory admits minimal supersymmetric compactifications if the internal manifold has exceptional holonomy. The inclusion of non-vanishing fluxes in M-theory and string theory compactifications induce a superpotential in the lower dimensional theory, which depends on the fluxes. In this work, we check the conjectured form of this superpotential in the case of warped M-theory compactifications on Spin(7) holonomy manifolds. We perform a Kaluza-Klein reduction of the eleven-dimensional supersymmetry transformation for the gravitino and we find by direct comparison the superpotential expression. We check the conjecture for the heterotic string compactified on a Calabi-Yau three-fold as well. The conjecture can be checked indirectly by inspecting the scalar potential obtained after the compactification of M-theory on Spin(7) holonomy manifolds with non-vanishing fluxes. The scalar potential can be written in terms of the superpotential and we show that this potential stabilizes all the moduli fields describing deformations of the metric except for the radial modulus. All the above analyses require the knowledge of the minimal supergravity action in three dimensions. Therefore we calculate the most general causal ,, =1 three-dimensional, gauge invariant action coupled to matter in superspace and derive its component form using Ectoplasmic integration theory. We also show that the three-dimensional theory which results from the compactification is in agreement with the more general supergravity construction. The compactification procedure takes into account higher order quantum correction terms in the low energy effective action. We analyze the properties of these terms on a Spin(7) background. We derive a perturbative set of solutions which emerges from a warped compactification on a Spin(7) holonomy manifold with non-vanishing flux for the M-theory field strength and we show that in general the Ricci flatness of the internal manifold is lost, which means that the supergravity vacua are deformed away from the exceptional holonomy. Using the superpotential form we identify the supersymmetric vacua out of this general set of solutions. [source] Lesions of the mammillary body region alter hippocampal movement signals and theta frequency: Implications for path integration modelsHIPPOCAMPUS, Issue 9 2008Patricia E. Sharp Abstract Cells throughout the hippocampal formation are involved in processing spatial information. These same cells also show an influence of locomotor activity, and these movement signals are thought to be critical for the path integration abilities of these cells. Nuclei in the mammillary region provide ascending influences to the hippocampal formation and have been implicated in influencing both hippocampal spatial and theta signals. Here, we report the effects of mammillary lesions on movement-related signals in several hippocampal subregions. We find first, as predicted by earlier work, these lesions cause an approximately 1 Hz reduction in the frequency of theta modulation of cell firing. According to recent theoretical work, this might, in turn, be expected to influence the size of hippocampal place fields. Our data do not confirm this prediction for any of the hippocampal regions examined. Second, we report lesion effects on the relationship between firing rate and running speed for the hippocampal cells. These lesions caused a reduction in both the slope and intercept of rate-by-speed functions for cells in the hippocampus and postsubiculum. Surprisingly, cells in subiculum showed an opposite effect, so that the excitatory influence of locomotion was enhanced. Path integration theories predict that the speed at which path integration occurs is related to the strength of this movement signal. In remarkable accordance with this prediction, we report that the timing of the place cell signals is slowed following mammillary lesions for hippocampal and postsubicular cells, but, in contrast, is speeded up for subicular cells. In fact, the timing for place signals across lesion condition and brain region is predicted by a single linear function which relates timing to the strength of the running speed signal. Thus, these data provide remarkable support for some aspects of current path integration theory, while posing a challenge for other aspects of these same theories. © 2008 Wiley-Liss, Inc. [source] Across the EU Studies,New Regionalism Frontier: Invitation to a DialogueJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 4 2010ALEX WARLEIGH-LACK This article notes a lack of communication between two broad schools of scholarship on regional integration: EU studies and analyses of the ,new regionalism'. It is argued that the existence of this divide, which is perpetrated by proponents of both schools, is an impediment to the elaboration of useful theory as well as being a missed opportunity. The benefits and problems of using the EU as a comparator in studies of regionalism are assessed. While the mistake of giving the EU analytical primacy as a benchmark or model is to be avoided, it is argued that careful treatment of accumulated insights from EU studies (including a proper re-inspection of classical integration theory) brings clear methodological and meta-theoretical benefits for the project of comparative regional integration scholarship. [source] Europeanization and Globalization: The Missing LinkJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 5 2001Marjoleine Hennis European integration theory is currently dominated by a debate about the role of domestic changes, state-society relations, and policy networks within Europe. This article seeks to contribute to this debate by dealing with what is understood as a generally poor conceptualization of the interaction between globalization and Europeanization. A framework is offered which takes account of the impact of globalization on the underlying economic structure and on European regulation. It is argued that only such a comprehensive approach can provide a greater insight into the development of European integration. These issues are addressed through the analysis of the common agricultural policy (CAP). [source] The Governance Approach to European IntegrationJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 2 2001Markus Jachtenfuchs This article argues that the study of European integration is divided into two distinct approaches: classical integration theory for which the shape of the Euro-polity is the dependent variable; and the governance approach for which it is the independent variable. An historical and conceptual overview of the approach focuses on the efficiency side of governance and excludes issues of democracy and legitimacy. From a sociology of knowledge perspective, the first part traces the roots of the present discussion back to three bodies of literature, namely studies on Europeanization, regulatory policy-making and network concepts. The second part presents the achievements of the approach: putting EU studies in a comparative perspective, directing attention towards democratic governance and bypassing old dichotomies on the future of the nation-state. The final section evaluates present shortcomings, most notably a bias toward problem-solving, the proliferation of case studies and the lack of a coherent theoretical perspective. [source] Coping With Uncertainties in Advance Care PlanningJOURNAL OF COMMUNICATION, Issue 3 2001Stephen C. Hines This essay extends problematic integration theory and related theories of uncertainty management to communication about serious illness and death. These extensions (a) note that theorizing must focus on multiple, interrelated uncertainties rather than a single such uncertainty; (b) explain how communication with others often problematizes efforts to cope with illness-related uncertainties; and (c) identify specific factors that may influence how persons choose to cope with these uncertainties. The essay describes implications for ongoing efforts to improve communication with persons nearing death. Specifically, they point to 5 incorrect assumptions that limit the effectiveness of current efforts to encourage persons to talk about their end-of-life preferences with others in a process referred to as advance care planning and then suggest concrete changes derived from this framework that can improve the advance care planning process and enhance the quality of end-of- life care. [source] | ||||||||||