906 resultados para Interhemispheric Facilitation


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Contrary to a commonly held belief that broiler chickens need more space, there is increasing evidence that these birds are attracted to other birds. Indeed, commercially farmed birds exhibit a range of socially facilitated behaviours, such as increased feeding and preening in response to the presence of other birds. Social facilitation can generate feedback loops, whereby the adoption of a particular behaviour can spread rapidly and suddenly through the population. Here, by measuring the rate at which broiler chickens join and leave a feeding trough as a function of the number of birds already there, we quantify social facilitation. We use these measurements to parameterize a simulation model of chicken feeding behaviour. This model predicts, and further observations of broiler chickens confirm, that social facilitation leads to excitatory and synchronized patterns of group feeding. Such models could prove a powerful tool in understanding how feeding patterns depend on broiler house design.

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The effect of vision on the excitability of corticospinal projections to the flexor carpi radialis (FCR) and extensor carpi radialis (ECR) muscles of right human forearm was investigated before and during discrete movement of the opposite limb. An external force opposed the initial phase of the movement (wrist flexion) and assisted the reverse phase, so that recruitment of the wrist extensors was minimized. Three conditions were used as follows: viewing the inactive right limb (Vision), viewing the mirror image of the moving left limb (Mirror), and with vision of the right limb occluded (No Vision). Transcranial magnetic stimulation was delivered to the left motor cortex: before, at the onset of, or during the left limb movement to obtain motor evoked potentials (MEPs) in the muscles of the right forearm. At and following movement onset, MEPs obtained in the right FCR were smaller in the Vision condition than in the Mirror and No Vision conditions. A distinct pattern of variation was obtained for the ECR. In all conditions, MEPs in this muscle were elevated upon or following movement of the opposite limb. An additional analysis of ipsilateral silent periods indicated that interhemispheric inhibition plays a role in mediating these effects. Activity-dependent changes in corticospinal output to a resting limb during discrete actions of the opposite limb are thus directly contingent upon where one looks. Furthermore, the extent to which vision exerts an influence upon projections to specific muscles varies in accordance with the functional contribution of their homologs to the intended action.

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The relationships among organisms and their surroundings can be of immense complexity. To describe and understand an ecosystem as a tangled bank, multiple ways of interaction and their effects have to be considered, such as predation, competition, mutualism and facilitation. Understanding the resulting interaction networks is a challenge in changing environments, e.g. to predict knock-on effects of invasive species and to understand how climate change impacts biodiversity. The elucidation of complex ecological systems with their interactions will benefit enormously from the development of new machine learning tools that aim to infer the structure of interaction networks from field data. In the present study, we propose a novel Bayesian regression and multiple changepoint model (BRAM) for reconstructing species interaction networks from observed species distributions. The model has been devised to allow robust inference in the presence of spatial autocorrelation and distributional heterogeneity. We have evaluated the model on simulated data that combines a trophic niche model with a stochastic population model on a 2-dimensional lattice, and we have compared the performance of our model with L1-penalized sparse regression (LASSO) and non-linear Bayesian networks with the BDe scoring scheme. In addition, we have applied our method to plant ground coverage data from the western shore of the Outer Hebrides with the objective to infer the ecological interactions. (C) 2012 Elsevier B.V. All rights reserved.

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Objective: to identify non-invasive interventions in the perinatal period that could enable midwives to offer effective support to women within the area of maternal mental health and well-being.

Methods: a total of 9 databases were searched: MEDLINE, PubMed, EBSCO (CINAHL/British Nursing Index), MIDIRS Online Database, Web of Science, The Cochrane library, CRD (NHS EED/DARE/HTA), Joanne Briggs Institute and EconLit. A systematic search strategy was formulated using key MeSH terms and related text words for midwifery, study aim, study design and mental health. Inclusion criteria were articles published from 1999 onwards, English language publications and articles originating from economically developed countries, indicated by membership of the Organisation for Economic Co-operation and Development (OECD). Data were independently extracted using a data collection form, which recorded data on the number of papers reviewed, time frame of the review, objectives, key findings and recommendations. Summary data tables were set up outlining key data for each study and findings were organised into related groups. The methodological quality of the reviews was assessed based on predefined quality assessment criteria for reviews.

Findings: 32 reviews were identified as examining interventions that could be used or co-ordinated by midwives in relation to some aspect of maternal mental health and well-being from the antenatal to the postnatal period and met the inclusion criteria. The review highlighted that based on current systematic review evidence it would be premature to consider introducing any of the identified interventions into midwifery training or practice. However there were a number of examples of possible interventions worthy of further research including midwifery led models of care in the prevention of postpartum depression, psychological and psychosocial interventions for treating postpartum depression and facilitation/co-ordination of parent-training programmes. No reviews were identified that supported a specific midwifery role in maternal mental health and well-being in pregnancy, and yet, this is the point of most intensive contact.

Key conclusions and implications for practice: This systematic review of systematic reviews provides a valuable overview of the current strengths and gaps in relation to maternal mental health interventions in the perinatal period. While there was little evidence identified to inform the current role of midwives in maternal mental health, the review provides the opportunity to reflect on what is achievable by midwives now and in the future and the need for high quality randomised controlled trials to inform a strategic approach to promoting maternal mental health in midwifery.

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Language deficits are frequently reported in studies of patients with schizophrenia. The present study sought to test the hypothesis that such deficits are related to callosal function in this group. The FAS test of verbal fluency and Perin's Spoonerisms test of phonological processing were the tests of language. Callosal function was assessed using a Crossed Finger Localisation Test (CFLT), which is a measure of the interhemispheric transfer of somatosensory information. Patients with schizophrenia performed less well than controls on measures of language function. as well as on the CFLT. Significant positive correlations between CFLT performance and language function were present in the patient group, but not the control group. These findings extend on previous studies that report functional abnormalities of the corpus callosum in schizophrenia and are consistent with the hypothesis that language deficits in schizophrenia are related to impaired callosal functioning in this group. However, other explanations cannot be ruled Out.

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In order to investigate cytolytic activity in the testis of Fasciola hepatica, flukes belonging to several different triclabendazole (TCBZ)-sensitive and TCBZ-resistant isolates, and wildtype flukes from field infections, were studied by light and electron microscopy with a view to identifying sites of heterophagy and macromolecular hydrolysis. At the periphery of the testis tubules in all the flukes examined, large euchromatic nuclei, each bearing a prominent nucleolus, were seen. These were invested with a thin cytoplasmic layer, extensions of which partially enveloped and probably supported the neighbouring spermatogonia. No lateral cell boundaries were identified in this tissue, possibly indicating syncytial organisation. The tissue, considered to be analogous to Sertoli cells in vertebrate testis, was identified as sustentacular tissue. It displayed cytoplasmic features consistent with protein/glycoprotein synthesis (through a granular endoplasmic reticulum-Golgi mediated mechanism) and intracellular digestion/heterophagy (through a lysosomal system). The intracytoplasmic hydrolytic activity of the sustentacular tissue probably serves to scavenge effete cells and cytoplasmic debris, to recycle useful molecules, to promote spermatozoon maturation and possibly to aid osmoregulation within the tubules. Certain protein-containing macromolecules synthesised in the sustentacular tissue may contribute to the seminiferous fluid, or have pheromonal activity. The presence of numerous mitochondria and abundant smooth endoplasmic reticulum is consistent with facilitation of inward and outward movement of micromolecular nutrients, metabolites including excretory products and water. In the sustentacular tissue of certain flukes with dysfunctional spermiogenesis, there was increased heterophagic and cytolytic scavenging activity. The cytoplasmic residual vacuoles remaining after the release of spermatids were also identified as possible sites for lysosome-mediated intracellular digestion and osmoregulation in the testis tubules of F. hepatica. (C) 2012 Elsevier B.V. All rights reserved.

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Cross education is the process whereby training of one limb gives rise to enhancements in the performance of the opposite, untrained limb. Despite interest in this phenomenon having been sustained for more than a century, a comprehensive explanation of the mediating neural mechanisms remains elusive. With new evidence emerging that cross education may have therapeutic utility, the need to provide a principled evidential basis upon which to design interventions becomes ever more pressing. Generally, mechanistic accounts of cross education align with one of two explanatory frameworks. Models of the 'cross activation' variety encapsulate the observation that unilateral execution of a movement task gives rise to bilateral increases in corticospinal excitability. The related conjecture is that such distributed activity, when present during unilateral practice, leads to simultaneous adaptations in neural circuits that project to the muscles of the untrained limb, thus facilitating subsequent performance of the task. Alternatively, 'bilateral access' models entail that motor engrams formed during unilateral practise, may subsequently be utilised bilaterally - that is, by the neural circuitry that constitutes the control centres for movements of both limbs. At present there is a paucity of direct evidence that allows the corresponding neural processes to be delineated, or their relative contributions in different task contexts to be ascertained. In the current review we seek to synthesise and assimilate the fragmentary information that is available, including consideration of knowledge that has emerged as a result of technological advances in structural and functional brain imaging. An emphasis upon task dependency is maintained throughout, the conviction being that the neural mechanisms that mediate cross education may only be understood in this context. © 2013 Ruddy and Carson.

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Purpose

To be effective, definitions of elder abuse should be informed by the perspectives of older people themselves.

Methods

This qualitative study used data from eight focus groups involving 58 people aged over 65 years in both urban and rural settings across Northern Ireland and the Republic of Ireland. Following training, four older people assisted in facilitation and analysis as ‘peer-researchers'.

Findings

Increasing lack of respect within society was experienced as abusive. The vulnerability of older people to abuse was perceived as relating to the need for help and support, where standing up for themselves might have repercussions for the person's health or safety. Emotional abusiveness was viewed as underpinning all forms of abuse, and as influencing its experienced severity. Respondents' views as to whether an action was abusive required an understanding of intent; some actions that professionals might view as abusive were regarded as acceptable if they were in the older person's best interests.

Implications

Preventing abuse requires a wide-ranging approach including re-building respect for older people within society. Procedures to prevent elder abuse need to take into account the emotional impact of family relationships and intent, not just a description of behaviours that have occurred.

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‘Temporally urgent’ reactions are extremely rapid, spatially precise movements that are evoked following discrete stimuli. The involvement of primary motor cortex (M1) and its relationship to stimulus intensity in such reactions is not well understood. Continuous theta burst stimulation (cTBS) suppresses focal regions of the cortex and can assess the involvement of motor cortex in speed of processing. The primary objective of this study was to explore the involvement of M1 in speed of processing with respect to stimulus intensity. Thirteen healthy young adults participated in this experiment. Behavioral testing consisted of a simple button press using the index finger following median nerve stimulation of the opposite limb, at either high or low stimulus intensity. Reaction time was measured by the onset of electromyographic activity from the first dorsal interosseous (FDI) muscle of each limb. Participants completed a 30 min bout of behavioral testing prior to, and 15 min following, the delivery of cTBS to the motor cortical representation of the right FDI. The effect of cTBS on motor cortex was measured by recording the average of 30 motor evoked potentials (MEPs) just prior to, and 5 min following, cTBS. Paired t-tests revealed that, of thirteen participants, five demonstrated a significant attenuation, three demonstrated a significant facilitation and five demonstrated no significant change in MEP amplitude following cTBS. Of the group that demonstrated attenuated MEPs, there was a biologically significant interaction between stimulus intensity and effect of cTBS on reaction time and amplitude of muscle activation. This study demonstrates the variability of potential outcomes associated with the use of cTBS and further study on the mechanisms that underscore the methodology is required. Importantly, changes in motor cortical excitability may be an important determinant of speed of processing following high intensity stimulation.

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Base rate neglect on the mammography problem can be overcome by explicitly presenting a causal basis for the typically vague false-positive statistic. One account of this causal facilitation effect is that people make probabilistic judgements over intuitive causal models parameterized with the evidence in the problem. Poorly defined or difficult-to-map evidence interferes with this process, leading to errors in statistical reasoning. To assess whether the construction of parameterized causal representations is an intuitive or deliberative process, in Experiment 1 we combined a secondary load paradigm with manipulations of the presence or absence of an alternative cause in typical statistical reasoning problems. We found limited effects of a secondary load, no evidence that information about an alternative cause improves statistical reasoning, but some evidence that it reduces base rate neglect errors. In Experiments 2 and 3 where we did not impose a load, we observed causal facilitation effects. The amount of Bayesian responding in the causal conditions was impervious to the presence of a load (Experiment 1) and to the precise statistical information that was presented (Experiment 3). However, we found less Bayesian responding in the causal condition than previously reported. We conclude with a discussion of the implications of our findings and the suggestion that there may be population effects in the accuracy of statistical reasoning.

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People often struggle when making Bayesian probabilistic estimates on the basis of competing sources of statistical evidence. Recently, Krynski and Tenenbaum (Journal of Experimental Psychology: General, 136, 430–450, 2007) proposed that a causal Bayesian framework accounts for peoples’ errors in Bayesian reasoning and showed that, by clarifying the causal relations among the pieces of evidence, judgments on a classic statistical reasoning problem could be significantly improved. We aimed to understand whose statistical reasoning is facilitated by the causal structure intervention. In Experiment 1, although we observed causal facilitation effects overall, the effect was confined to participants high in numeracy. We did not find an overall facilitation effect in Experiment 2 but did replicate the earlier interaction between numerical ability and the presence or absence of causal content. This effect held when we controlled for general cognitive ability and thinking disposition. Our results suggest that clarifying causal structure facilitates Bayesian judgments, but only for participants with sufficient understanding of basic concepts in probability and statistics.

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This chapter explores how the EU is a largely overlooked exporter of normative power through its facilitation and use of clinical trials data produced abroad for the marketing of safe pharmaceuticals at home; a move that helps to foster the growing resort to pharmaceuticals as a fix for public health problems. This is made possible by the EU’s (de)selection of international ethical frameworks in preference to the international technical standards it co-authors with other global regulators. Clinical trials abroad underscore how ethics are contingent and revisable in light of market needs, producing weak protections for the vulnerable subjects of EU law. I argue that these components and effects of the regime are ultimately about that which undergirds, shapes and directs regulatory design. That is, I point to the use, infiltration, perpetuation and extension of market-oriented ideas, values and rationalities into formally non-market domains like biomedical knowledge production and public health. I explain how these are central to efforts at producing and legitimating the EU, its related imagined socio-political order based on a more innovative, profitable and competitive pharmaceutical sector in order to foster economic growth, jobs and prosperity, and with them the project of European integration. ‘Bioethics as risk’ is highlighted as a way to reshape and redirect the regulatory regime in ways that are more consistent with the spirit and letter of the ethical standards (and through them the human rights) the EU claims to uphold.

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Objectives: The Liverpool Care Pathway for the dying patient (LCP) was designed to improve end-of-life care in generalist health care settings. Controversy has led to its withdrawal in some jurisdictions. The main objective of this research was to identify the influences that facilitated or hindered successful LCP implementation.

Method: An organisational case study using realist evaluation in one health and social care trust in Northern Ireland. Two rounds of semi-structured interviews were conducted with two policy makers and twenty two participants with experience and/or involvement in management of the LCP during 2011 and 2012.

Results: Key resource inputs included facilitation with a view to maintaining LCP ‘visibility’, reducing anxiety among nurses and increasing their confidence regarding the delivery of end-of-life care; and nurse and medical education designed to increase professional self-efficacy and reduce misuse and misunderstanding of the LCP. Key enabling contexts were consistent senior management support; ongoing education and training tailored to the needs of each professional group; and an organisational cultural change in the hospital setting that encompassed end-of-life care.

Conclusion: There is a need to appreciate the organizationally complex nature of intervening to improve end-of-life care. Successful implementation of evidence-based interventions for end-of-life care requires commitment to planning, training and ongoing review that takes account of different perspectives, institutional hierarchies and relationships and the educational needs of professional disciplines. There is a need also to recognise that medical consultants require particular support in their role as gatekeepers and as a lead communication channel with patients and their relatives.

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Background: Failure to recruit sufficient numbers of participants to randomized controlled trials is a common and serious problem. This problem may be additionally acute in music therapy research.

Objective: To use the experience of conducting a large randomized controlled trial of music therapy for young people with emotional and behavioral difficulties to illustrate the strategies that can be used to optimize recruitment; to report on the success or otherwise of those strategies; and to draw general conclusions about the most effective approaches.

Methods: Review of the methodological literature, and a narrative account and realist analysis of the recruitment process.

Results: The strategies adopted led to the achievement of the recruitment target of 250 subjects, but only with an extension to the recruitment period. In the pre-protocol stage of the research, these strategies included the engagement of non-music therapy clinical investigators, and extensive consultation with clinical stakeholders. In the protocol development and initial recruitment stages, they involved a search of systematic reviews of factors leading to under-recruitment and of interventions to promote recruitment, and the incorporation of their insights into the research protocol and practices. In the latter stages of recruitment, various stakeholders including clinicians, senior managers and participant representatives were consulted in an attempt to uncover the reasons for the low recruitment levels that the research was experiencing.

Conclusions: The primary mechanisms to promote recruitment are education, facilitation, audit and feedback, and time allowed. The primary contextual factors affecting the effectiveness of these mechanisms are professional culture and organizational support.

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Background: Queen's University Red Cross is a medical student-led volunteer group with a key aim of promoting social change within local communities and empowering young people to aspire to higher education. We describe ‘The Personal Development Certificate’, a 12–week community development programme devised by third-year medical students at Queen's University Belfast to target young people who are lacking educational motivation, are disengaged at home or are marginalised through social circumstances.

Context: Community-based education is of increasing importance within undergraduate and postgraduate medical education in the UK, and further afield. We evaluated the perceived improvements in key skills such as teamwork, leadership, communication, and problem solving in students following participation in this programme, and the extent to which their attitude and appreciation of community-based medicine changed.

Innovation: Following facilitation of this community-based initiative, all students reported a perceived improvement in the acquired skill sets. Students made strong links from this programme to previous clinical experiences and appreciated the opportunity to translate a series of classroom-learned skills to real-life environments and interactions. The students’ appreciation and understanding of community-based medicine was the single most improved area of our evaluation.

Implications: We have demonstrated that medical students possess the skills to develop and facilitate their own educational projects. Non-clinical, student-led community projects have the potential to be reproduced using recognised frameworks and guidelines to complement the current undergraduate medical curriculum