857 resultados para Senses and sensation


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A self-produced tactile stimulus is perceived as less ticklish than the same stimulus generated externally. We used fMRI to examine neural responses when subjects experienced a tactile stimulus that was either self-produced or externally produced. More activity was found in somatosensory cortex when the stimulus was externally produced. In the cerebellum, less activity was associated with a movement that generated a tactile stimulus than with a movement that did not. This difference suggests that the cerebellum is involved in predicting the specific sensory consequences of movements, providing the signal that is used to cancel the sensory response to self-generated stimulation.

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A main-chain nonracemic chiral liquid crystalline polymer was synthesized from (R)-(-)4'-{w-[2-(p-hydroxy-o-nitrophenyloxy)-1-propyloxy]-1-decyloxyl-4-biphenylcarboxylic acid. This polymer contained 10 methylene units in each chemical repeating unit and was abbreviated PET(R*-10). On the basis of differential scanning calorimetry, wide-angle X-ray diffraction, and polarized light microscopy experiments, chiral smectic C (S-C*) and chiral smectic A (S-A*) phases were identified. Both flat-elongated and helical lamellar crystal morphologies were observed in transmission electron microscopy. Of particular interest was the flat-elongated lamellar crystals were constructed via microtwinning of an orthorhombic cell with dimensions of a = 1.42 nm, b = 1.28 nm, and c = 3.04 nm. On the other hand, the helical lamellar crystals were exclusively left-handed, which was opposite to the right-handed helical crystals grown in PET(R*-9) and PET(R*-11) (having 9 and 11 methylene units, respectively). Note that these three polymers had identical right-handed chiral centers (R*-). Therefore, a single methylene unit difference on the polymer backbones on an atomic length scale substantially changed the chirality of the crystals in the micrometer length scale. Furthermore, aggregates of these helical crystals in PET(R*-10) did not generate banded spherulites in polarized light microscopy. Possible reasons for this change and loss of helical senses (handedness) on different length scales in chirality transferring processes were discussed.

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Rothwell, W., 'Synonymity and Semantic Variability in Medieval French and Middle English', Modern Language Review (2007) 102(2) pp.363-380 RAE2008

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The concept of attention has been used in many senses, often without clarifying how or why attention works as it does. Attention, like consciousness, is often described in a disembodied way. The present article summarizes neural models and supportive data and how attention is linked to processes of learning, expectation, competition, and consciousness. A key them is that attention modulates cortical self-organization and stability. Perceptual and cognitive neocortex is organized into six main cell layers, with characteristic sub-lamina. Attention is part of unified design of bottom-up, horizontal, and top-down interactions among indentified cells in laminar cortical circuits. Neural models clarify how attention may be allocated during processes of visual perception, learning and search; auditory streaming and speech perception; movement target selection during sensory-motor control; mental imagery and fantasy; and hallucination during mental disorders, among other processes.

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Addition of menthol to cigarettes may be associated with increased initiation of smoking. The potential mechanisms underlying this association are not known. Menthol, likely due to its effects on cold-sensing peripheral sensory neurons, is known to inhibit the sensation of irritation elicited by respiratory irritants. However, it remains unclear whether menthol modulates cigarette smoke irritancy and nicotine absorption during initial exposures to cigarettes, thereby facilitating smoking initiation. Using plethysmography in a C57Bl/6J mouse model, we examined the effects of L-menthol, the menthol isomer added to cigarettes, on the respiratory sensory irritation response to primary smoke irritants (acrolein and cyclohexanone) and smoke of Kentucky reference 2R4 cigarettes. We also studied L-menthol's effect on blood levels of the nicotine metabolite, cotinine, immediately after exposure to cigarette smoke. L-menthol suppressed the irritation response to acrolein with an apparent IC₅₀ of 4 ppm. Suppression was observed even at acrolein levels well above those necessary to produce a maximal response. Cigarette smoke, at exposure levels of 10 mg/m³ or higher, caused an immediate and marked sensory irritation response in mice. This response was significantly suppressed by L-menthol even at smoke concentrations as high as 300 mg/m³. Counterirritation by L-menthol was abolished by treatment with a selective inhibitor of Transient Receptor Potential Melastatin 8 (TRPM8), the neuronal cold/menthol receptor. Inclusion of menthol in the cigarette smoke resulted in roughly a 1.5-fold increase in plasma cotinine levels over those observed in mice exposed to smoke without added menthol. These findings document that, L-menthol, through TRPM8, is a strong suppressor of respiratory irritation responses, even during highly noxious exposures to cigarette smoke or smoke irritants, and increases blood cotinine. Therefore, L-menthol, as a cigarette additive, may promote smoking initiation and nicotine addiction.

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Based on meetings of the Society for Research into Higher Education’s Student Experience Network over the past three years, the genuinely open research question is posed whether there is one or more undergraduate student experience within English higher education. Answering this question depends on whether what is taught or what is learnt is examined. If the latter, then a unitary student experience can be said to exist only in the narrowest of normative senses. What undergraduates actually learn – defined in the widest sense – is the $64,000 question of research on the student experience. Various ways to answer this question are proposed, including using students to research students. Conceptual tools to apply to findings can be developed from youth studies and cognate disciplines, particularly in relation to student identities and aspirations. Lastly, these proposals are placed in the wider context of comparative models of the varieties of student experience, including those emerging in the UK’s national regions.

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A new kind of photographic representation, called movement-image is proposed and discussed to record the visual experience of the journey through urban highways. It consists of performing long exposure photographic shots while the track is traversed, thus registering a time-panorama which includes landscape signs and inner spaces of the ways involved. This proposal is linked to the limitations of representing these expressways, if they are understood as structures of instrumental origin, where the resulting experience comes from moving at high speed through the territory. In al almost all cases the aesthetic approach or urban integration with the city and landscape are excluded. In this sense, although such structures may be an opportunity to collect, build and colonize the urban landscape, the lack of adequate representation of the phenomenon causes a difficulty in its understanding and transformation. The options for representation using photography is assumed, knowing its own particular tradition in the use of long exposures, for the expression of the mobile, and the multiple visual attention, divided or weakened.

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Early experiences are of potential importance in shaping long-term behavior. This study examined the relative influence of prenatal and/or early postnatal experience of chemosensory stimuli on subsequent olfactory and dietary preferences of cats as newborns, at 9-10 weeks, and at 6 months. Cats were exposed to vanillin or 4-ethylguaiacol via their mother's diet either prenatally, postnatally, perinatally (prenatal and postnatal), or experienced no exposure to the stimuli (control). Newborns were given a two-choice olfactory test between the familiar "odor" and no odor; 9-10 week olds were tested for their preference between two food treats, one flavored with the familiar stimulus and the other unflavored; at 6 months, cats were given a choice of two bowls of food, one flavored with the familiar stimulus and the other unflavored. At all ages, cats preferred the familiar, and avoided the unfamiliar, stimulus. Perinatal exposure exerted the strongest influence on preference. Prenatal exposure influenced preference at all ages and postnatal exposure exerted a stronger effect as the cat aged. We conclude that long-term chemosensory and dietary preferences of cats are influenced by prenatal and early (nursing) postnatal experience, supporting a natural and biologically relevant mechanism for the safe transmission of diet from mother to young. © The Author 2012. Published by Oxford University Press. All rights reserved.

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When Muriel Rukeyser travelled to Gauley Bridge in 1936 to report on the industrial disaster that had led to the deaths of over 700 miners, her findings led her to write what is arguably her masterpiece – the 1938 poem series The Book of the Dead. Of all Rukeyser's writings, this hybrid work of documentary techniques and metaphors, of testimony and elegy, has attracted the most critical attention. However, analyses of the series have tended to focus on the ways in which the poet adopted and adapted documentary methods in order to offer a leftist ideological critique on capitalist-born social injustice. The purpose of this article is not to negate such readings, but to offer alongside them insight into a more ethical-philosophical approach that I believe guided Rukeyser's entire career. Via an examination of the ways in which Rukeyser employs the human senses to articulate the complexities of human political, metaphysical and social relations, this article explores the influence of the Zionist Martin Buber on the poet. Rukeyser acknowledged Buber's writings in her later work, but I contend here that they played a large part in the formation of her poetics, especially in connection with her documentary aesthetic. Whilst several critics have noted, albeit often superficially, the Marxist flavour of Rukeyser's poetry in The Book of the Dead, I argue for the influence of Buber over Marx in terms or responsibility, community and dialogue. Both Rukeyser's and Buber's methods of expressing and promoting these ethical necessities rely on a synaesthetic response to the world. Where Buber advances a dialogue between the self and alterity through transcendent personal encounter, Rukeyser locates such encounter in the poem, arguing for an exchange that leads to creation, and to personal and interpersonal growth.

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This article unpacks the variant meanings, perceptions, and experiences of violent enactment and stigmatic shaming among loyalists with regard to rejection, harm, and masking. What we locate is a landscape of variable emotions, experiences, neutralization techniques, dependences, and embedded forms of fatalism as well as resilience. Attending to those alternate positions and well-beings is important in considering the capacity of re-integration and the presently uneven nature of it. In adopting an account-driven format we present and analyze how involvement in violent conflict can, on the one hand, provoke persistence and senses of transitional thinking and on the other engender rejection and related fatalistic attitudes.

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The use of museum collections as a path to learning for university students is fast becoming a new pedagogy for higher education. Despite a strong tradition of using lectures as a way of delivering the curriculum, the positive benefits of ‘active’ and ‘experiential learning’ are being recognised in universities at both a strategic level and in daily teaching practice. As museum artefacts, specimens and art works are used to evoke, provoke, and challenge students’ engagement with their subject, so transformational learning can take place. This unique book presents the first comprehensive exploration of ‘object-based learning’ as a pedagogy for higher education in a broad context. An international group of authors offer a spectrum of approaches at work in higher education today. They explore contemporary principles and practice of object-based learning in higher education, demonstrating the value of using collections in this context and considering the relationship between academic discipline and object-based learning as a teaching strategy.

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Adolescence is a time of developmental transition that for one in five young people is characterised by feelings of oppositionality, rebellion, and negativism. Despite the prevalent experience of teen turbulence and despite its significance within the phenomenological framework provided by reversal theory (RT), the childhood antecedents of rebelliousness in adolescence and adulthood have not been given extensive empirical attention within RT, although such work has been carried out using other constructs and theories. We examined recalled parenting style, childhood adversity, and attachment style in adulthood as correlates of proactive and reactive rebelliousness in a sample of 80 participants, aged 18 to 50 years. Each participant responded to a questionnaire package containing the revised Adult Attachment Scale, the Parental Bonding Instrument, the Childhood Experience of Care and Abuse Questionnaire, and the Negativism Dominance Scale. We found that paternal abusive parenting, followed by paternal parenting style, paternal neglect, and paternal antipathy were independently predictive of scores on proactive rebelliousness, the sensation-seeking form. Maternal and paternal indifferent parenting styles each were found to equivalently and independently predict scores on reactive rebelliousness, the interpersonal disaffection form. The results of this study suggest these two forms of rebelliousness may have distinctly different antecedents. A longitudinal study is needed to examine the potentially causal pathways that are suggested by the results of this cross-sectional research. We consider reversal theory explanations of these results and contrast them with complementary theoretical frameworks.