217 research outputs found

    Movement, Action, and Situation: Presence in Virtual Environments

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    Presence is commonly defined as the subjective feeling of "being there". It has been mainly conceived of as deriving from immersion, interaction, and social and narrative involvement with suitable technology. We argue that presence depends on a suitable integration of aspects relevant to an agent's movement and perception, to her actions, and to her conception of the overall situation in which she finds herself, as well as on how these aspects mesh with the possibilities for action afforded in the interaction with the virtual environment

    A situated cognition perspective on presence

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    During interaction with computer-based 3-D simulations like virtual reality, users may experience a sense of involvement called presence. Presence is commonly defined as the subjective feeling of "being there". We discuss the state of the art in this inno vative research area and introduce a situated cognition perspective on presence. We argue that presence depends on the proper integration of aspects relevant to an agent's movement and perception, to her actions, and to her conception of the overall situ a tion in which she finds herself, as well as on how these aspects mesh with the possibilities for action afforded in the interaction with the artifact. We also aim at showing that studies of presence offer a test-bed for different theories of situated co gnition.

    The use of virtual environments for survey spatial ability evaluation in topographical disorientation

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    Due to their interactivity and to the sense of presence they afford, virtual environments constitute an interesting opportunity to study spatial cognition. In accordance with this perspective, we aimed to introduce a spatial test in virtual simulation in order to investigate the survey spatial ability in patients with topographical disorientation. To do this, we used the “planning in advance task” in a virtual environment that constitutes an effective procedure to experimentally evaluate survey maps. With this procedure we present the single case of a woman, with a right medial temporal lobe lesion, who shows a selective impairment in the acquisition of new spatial relationships. The patient’s performance in “planning in advance task” was compared with that of a control group made up of 40 female subjects matched for age and education. Results show how the patient revealed a significantly lower spatial performance when compared to the control group, demonstrating an inability to solve survey-type spatial tasks in complex virtual environments

    Joint commitment: An analysis of emotions and non-verbal behaviors

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    According to Margaret Gilbert, a joint commitment (JC) is a commitment of two or more agents, called the parties of the JC, to engage in a common project. Creating a JC often involves an explicit agreement, carried out in a conversa-tional interaction through overt communication. We ex-plored aspects of such interactions that can be considered as complementary to verbal exchanges, focusing on how a JC is managed by the parties by means of emotional and other non-verbal bodily expressions. We analyzed three phases of the JC lifecycle (creation, maintenance, and violation), and in particular the emotional reaction of the participants to two types of violations by the experimenter. In our analysis we used standardized tools such as the Ethological Coding System for Interviews, the Mind Reading Emotional Library, and the Facial Action Coding System. Our results show that certain non-verbal behaviors in the phase of JC creation are characteristic of the participants who later did not fulfill their commitment. Moreover, the participants’ emotional reactions to JC violation by the experimenter turned out to depend on the type of violation. Finally, the creation and maintenance of JC, and the emotional reaction to its violation, appear to be independent of the participants’ personality and empathic disposition

    The Neuropsychiatric Inventory-Diary Rating Scale (NPI-Diary): A Method for Improving Stability in Assessing Neuropsychiatric Symptoms in Dementia

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    Background: In health-care settings, the use of the Neuropsychiatric Inventory-Nursing Home (NPI-NH) may not always be consistent with the authors’ guidelines, which affects its reliability. To avoid this bias, a diary version of the NPI (NPI-Diary) was developed. Aims: This study aimed to evaluate the psychometric properties (internal consistency and reliability) of the NPI-Diary, and examined its convergence with the NPI-NH. Methods: Two raters administered the NPI-NH and NPI-Diary to 40 participants with Alzheimer’s disease, selected randomly from a hospital’s weekly turnover. Results: The NPI-Diary exhibited adequate internal consistency (total: α = 0.581) and test-retest reliability (total: ρ = 0.711; p < 0.01). The interrater reliability values (ICC) for the NPI-NH and NPI-Diary differed significantly (Total: NPI-NH ICC = 0.506, NPI-Diary ICC = 0.879; Frequency: NPI-NH ICC = 0.51, NPI-Diary ICC = 0.798; Severity: NPI-NH ICC = 0.491, NPI-Diary ICC = 0.809). The convergent validity between the two inventories was also significant (total: ρ = 0.48; p < 0.01). Conclusions: The NPI-Diary showed more appropriate validity and reliability compared to the NPI-NH, when administered in a highly variable sample, as is generally the case in the current health-care setting

    Fetal oxygenation in the last weeks of pregnancy evaluated through the umbilical cord blood gas analysis

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    IntroductionEmbryo and fetus grow and mature over the first trimester of pregnancy in a dynamic hypoxic environment, where placenta development assures an increased oxygen availability. However, it is unclear whether and how oxygenation changes in the later trimesters and, more specifically, in the last weeks of pregnancy.MethodsObservational study that evaluated the gas analysis of the umbilical cord blood collected from a cohort of healthy newborns with gestational age >= 37 weeks. Umbilical venous and arterial oxygen levels as well as fetal oxygen extraction were calculated to establish whether oxygenation level changes over the last weeks of pregnancy. In addition, fetal lactate, and carbon dioxide production were analyzed to establish whether oxygen oscillations may induce metabolic effects in utero.ResultsThis study demonstrates a progressive increase in fetal oxygenation levels from the 37th to the 41st weeks of gestation (mean venous PaO2 approximately from 20 to 25 mmHg; p < 0.001). This increase is largely attributable to growing umbilical venous PaO2, regardless of delivery modalities. In neonates born by vaginal delivery, the increased oxygen availability is associated with a modest increase in oxygen extraction, while in neonates born by cesarean section, it is associated with reduced lactate production. Independently from the type of delivery, carbon dioxide production moderately increased. These findings suggest a progressive shift from a prevalent anaerobic metabolism (Warburg effect) towards a growing aerobic metabolism.ConclusionThis study confirms that fetuses grow in a hypoxic environment that becomes progressively less hypoxic in the last weeks of gestation. The increased oxygen availability seems to favor aerobic metabolic shift during the last weeks of intrauterine life; we hypothesize that this environmental change may have implications for fetal maturation during intrauterine life

    AS TEORIAS DE CURRÍCULO NA IMPLEMENTAÇÃO DAS BRINQUEDOTECAS NA PRIMEIRÍSSIMA INFÂNCIA: CONTRIBUIÇÕES DA NEUROPSICOLOGIA

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    HĂĄ algum tempo sĂŁo conhecidas as relaçÔes que permeiam a brincadeira e aprendizagem, sobretudo quando sistematizadas nos espaços das brinquedotecas e na organização dos  currĂ­culos escolares que incentivam e fomentam o desenvolvimento fĂ­sico, cognitivo, criativo, social e a linguagem da criança.  Mais recentemente, os estudos da neurociĂȘncia tem permitido evidenciar, por meio do uso das imagens por ressonĂąncia magnĂ©tica, como ocorrem os processos de aprendizagem e a sua relação com as oportunidades oferecidas Ă s crianças, assim sugerem o papel dos objetos e das relaçÔes das crianças com outras pessoas e com o ambiente onde vivem, sendo fulcrais para seu pleno desenvolvimento e crescimento. Neste texto, sĂŁo analisadas as relaçÔes entre as teorias do currĂ­culo, os objetos lĂșdicos e contribuiçÔes da neurociĂȘncia. Tais interaçÔes possibilitam cada vez mais, a reorganização do sistema neural em desenvolvimento que, no caso da primeirĂ­ssima infĂąncia, parece ser otimizĂĄvel com a quantidade de construçÔes de aprendizagem desses sujeitos nas brinquedotecas. Ao final, parece ser possĂ­vel inferir que esses espaços didĂĄticos de aprendizagem devem ocupar um lugar privilegiado nas prĂĄticas escolares e curriculares da primeira infĂąncia.

    Patient-Reported Outcomes After Swallowing (SWOARs)-Sparing IMRT in Head and Neck Cancers: Primary Results from a Prospective Study Endorsed by the Head and Neck Study Group (HNSG) of the Italian Association of Radiotherapy and Clinical Oncology (AIRO)

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    Objectives To prospectively investigate changes in M.D. Anderson Dysphagia Inventory (MDADI) scores in patients affected by naso- and oropharynx cancer after definitive radiochemotherapy (ChemoRT) using swallowing organs at risk (SWOARs)-sparing IMRT. Methods MDADI questionnaires were collected at baseline and at 6 and 12 months after treatment. MDADI scores were categorized as follows: >= 80 "optimal," 80-60 "adequate," < 60 "poor" deglutition-related quality of life (QoL) group, and dichotomized as "optimal" vs "adequate/poor" for the analysis. A mean MDADI composite (MDADI-C) change of 10 points was considered as minimal clinically important difference (MCID). Results Sixty-three patients were enrolled of which 47 were considered for the analysis. At baseline, 26 (55%) were "optimal" and 21 (45%) were "adequate/poor." The mean baseline MDADI-C score was 93.6 dropping to 81 at 6 months (p = 0.013) and slightly rising to 85.5 at 12 months (p = 0.321) for the "optimal" group. Indeed, the mean baseline MDADI-C score was 64.3 rising to 77.5 at 6 months (p = 0.006) and stabilizing at 76 at 12 months (p = 0.999) for the "adequate/poor" group. A statistically significant but not clinically relevant worsening of the MDADI-C score was reported for the "optimal" group, whereas both a statistically significant and clinically meaningful improvement of the MDADI-C score were reported for the "adequate/poor" group from before to post-treatment. Conclusion Our results suggest a doubly clinical benefit of dose optimization to SWOARs to minimize the RT sequalae in patients with a baseline "optimal" deglutition-related QoL and to recover from cancer dysphagia in those with a baseline "adequate/poor" deglutition-related QoL

    A virtual reality extended neuropsychological assessment for topographical disorientation: a feasibility study

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    <p>Abstract</p> <p>Background</p> <p>Topographical disorientation represents one of the main consequences of brain injury. Up to now several methodological approaches have been used in the assessment of the brain injured patient's navigational abilities showing a moderate correlation with the impairments observed in everyday contexts.</p> <p>Methods</p> <p>We propose a combination of standardized neuropsychological tests and a more situated virtual reality-based assessment for the evaluation of spatial orientation in brain injured patients.</p> <p>Results</p> <p>When tested with this virtual reality integrated procedure patients showed performance and execution times congruent with their neuropsychological evaluation. When compared to a control group, patients revealed significantly slower times and greater errors in solving virtual reality based spatial tasks.</p> <p>Conclusion</p> <p>The use of virtual reality, when combined with classical neuropsychological tests, can provide an effective tool for the study of topographical disorientation.</p
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