991 resultados para sensory perception
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Although research has documented the importance of emotion in risk perception, little is knownabout its prevalence in everyday life. Using the Experience Sampling Method, 94 part-timestudents were prompted at random via cellular telephones to report on mood state and threeemotions and to assess risk on thirty occasions during their working hours. The emotions valence, arousal, and dominance were measured using self-assessment manikins (Bradley &Lang, 1994). Hierarchical linear models (HLM) revealed that mood state and emotions explainedsignificant variance in risk perception. In addition, valence and arousal accounted for varianceover and above reason (measured by severity and possibility of risks). Six risks were reassessedin a post-experimental session and found to be lower than their real-time counterparts.The study demonstrates the feasibility and value of collecting representative samples of data withsimple technology. Evidence for the statistical consistency of the HLM estimates is provided inan Appendix.
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Objectifs¦? Connaître le vécu des médecins face à des patients ayant une faible littératie en¦santé (FLS)¦? Savoir de quelle façon les médecins s'y prennent pour détecter ces patients¦? Comprendre quels sont les problèmes rencontrés avec de tels patients¦? Connaître les stratégies utilisées pour faire face à cette situation¦? Découvrir ce qui pourrait aider les médecins à mieux détecter cette problématique¦chez leurs patients et à surmonter plus aisément les problèmes qui en découlent¦Méthode¦Enquête auprès de 47 médecins de famille de Suisse romande au travers d'un¦questionnaire élaboré à partir d'entretiens avec cinq médecins de la région et validé par¦ceux-ci ; analyse mixte quantitative et qualitative.¦Résultats¦? Les médecins de famille sont conscients de cette problématique (58% y sont¦confrontés quotidiennement).¦? La FLS représente une certaine charge dans leur pratique quotidienne (pour 68%¦des médecins).¦? La majorité (70%) des praticiens pense avoir les outils et compétences nécessaires¦pour gérer la situation.¦? Un grand nombre aimerait cependant en acquérir de nouveaux (entre 38% et 75%¦selon les outils).¦? Les médecins ont tendance à sous-estimer la prévalence des patients avec une¦FLS.¦? 60% des praticiens seraient intéressés par des outils de dépistage.¦Discussion et conclusion¦La FLS est une problématique importante au cabinet du médecin de famille, ayant de¦nombreuses conséquences sur la santé du patient. Nos résultats montrent, en¦concordance avec la littérature, qu'il est essentiel de dépister la FLS chez les patients et¦d'apporter de nouveaux outils aux praticiens afin de les aider dans la gestion de cette¦situation. Diverses interventions pourraient être mises en place afin d'améliorer la prise en¦charge de ces patients:¦? une introduction à la littératie en santé durant le parcours universitaire¦? un enseignement pratique lors de la formation post-graduée¦? un manuel d'information pour le praticien visant à l'aider dans cette problématique¦et à lui proposer des questions de dépistage¦? des brochures d'explications simples et illustrées à l'intention des patients
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Evidence of multisensory interactions within low-level cortices and at early post-stimulus latencies has prompted a paradigm shift in conceptualizations of sensory organization. However, the mechanisms of these interactions and their link to behavior remain largely unknown. One behaviorally salient stimulus is a rapidly approaching (looming) object, which can indicate potential threats. Based on findings from humans and nonhuman primates suggesting there to be selective multisensory (auditory-visual) integration of looming signals, we tested whether looming sounds would selectively modulate the excitability of visual cortex. We combined transcranial magnetic stimulation (TMS) over the occipital pole and psychophysics for "neurometric" and psychometric assays of changes in low-level visual cortex excitability (i.e., phosphene induction) and perception, respectively. Across three experiments we show that structured looming sounds considerably enhance visual cortex excitability relative to other sound categories and white-noise controls. The time course of this effect showed that modulation of visual cortex excitability started to differ between looming and stationary sounds for sound portions of very short duration (80 ms) that were significantly below (by 35 ms) perceptual discrimination threshold. Visual perceptions are thus rapidly and efficiently boosted by sounds through early, preperceptual and stimulus-selective modulation of neuronal excitability within low-level visual cortex.
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The objective of this study was to find out the relationship between students’ perception of Social Studies and their academic performance in the subject in Colleges of Education in Kaduna State. The respondents of the study comprised NCE 2 and NCE 3 students of Social Studies at the Federal College of Education in Zaria and the Kaduna State College of Education in Gidan Waya. The data for the study was collected using a questionnaire with reliability coefficient of 0.87. The Pearson’s Product Moment Correlation Coefficient was used to test the hypotheses formulated for the study. The hypotheses were tested at 0.05 level of significance with df = 232. The findings were as follows: 1. The Social Studies students in colleges of education in Kaduna State do not record high academic performance in the subject. 2. Students’ perception of the Social Studies curriculum does affect their academic performance in the subject 3. Students’ perception of relevance of Social Studies education has no bearing on their academic performance in the subject. 4. Students’ perception of public attitude towards Social Studies has no impact on their academic performance in the subject. 5. Students’ general perception of Social Studies does not affect their academic performance in the subject. Based on these findings the following recommendations were proffered for Social Studies researchers and policy makers. a. There is need for further research in order to determine the actual cause of students’ failure to display high performance in Social Studies. b. The NCE Social Studies curriculum should be reviewed in terms of volume and difficulty.
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Accurate perception of the order of occurrence of sensory information is critical for the building up of coherent representations of the external world from ongoing flows of sensory inputs. While some psychophysical evidence reports that performance on temporal perception can improve, the underlying neural mechanisms remain unresolved. Using electrical neuroimaging analyses of auditory evoked potentials (AEPs), we identified the brain dynamics and mechanism supporting improvements in auditory temporal order judgment (TOJ) during the course of the first vs. latter half of the experiment. Training-induced changes in brain activity were first evident 43-76 ms post stimulus onset and followed from topographic, rather than pure strength, AEP modulations. Improvements in auditory TOJ accuracy thus followed from changes in the configuration of the underlying brain networks during the initial stages of sensory processing. Source estimations revealed an increase in the lateralization of initially bilateral posterior sylvian region (PSR) responses at the beginning of the experiment to left-hemisphere dominance at its end. Further supporting the critical role of left and right PSR in auditory TOJ proficiency, as the experiment progressed, responses in the left and right PSR went from being correlated to un-correlated. These collective findings provide insights on the neurophysiologic mechanism and plasticity of temporal processing of sounds and are consistent with models based on spike timing dependent plasticity.
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An open prospective study was conducted among the patients visiting an urban medical policlinic for the first time without an appointment to assess whether the immigrants (who represent more than half of our patients) are aware of the health effects of smoking, whether the level of acculturation influences knowledge, and whether doctors give similar advice to Swiss and foreign smokers. 226 smokers, 105 Swiss (46.5%), and 121 foreign-born (53.5%), participated in the study. 32.2% (95% CI [24.4%; 41.1%]) of migrants and 9.6% [5.3%; 16.8%] of Swiss patients were not aware of negative effects of smoking. After adjustment for age, the multivariate model showed that the estimated odds of "ignorance of health effects of smoking" was higher for people lacking mastery of the local language compared with those mastering it (odds ratio (OR) = 7.5 [3.6; 15.8], p < 0.001), and higher for men (OR = 4.3 [1.9; 10.0], p < 0.001). Advice to stop smoking was given with similar frequency to immigrants (31.9% [24.2%; 40.8%] and Swiss patients (29.0% [21.0%; 38.5%]). Nonintegrated patients did not appear to receive less counselling than integrated patients (OR = 1.1 [0.6; 2.1], p = 0.812). We conclude that the level of knowledge among male immigrants not integrated or unable to speak the local language is lower than among integrated foreign-born and Swiss patients. Smoking cessation counselling by a doctor was only given to a minority of patients, but such counselling seemed irrespective of nationality.
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Intuitively, we think of perception as providing us with direct cognitive access to physical objects and their properties. But this common sense picture of perception becomes problematic when we notice that perception is not always veridical. In fact, reflection on illusions and hallucinations seems to indicate that perception cannot be what it intuitively appears to be. This clash between intuition and reflection is what generates the puzzle of perception. The task and enterprise of unravelling this puzzle took, and still takes, centre stage in the philosophy of perception. The goal of my dissertation is to make a contribution to this enterprise by formulating and defending a new structural approach to perception and perceptual consciousness. The argument for my structural approach is developed in several steps. Firstly, I develop an empirically inspired causal argument against naïve and direct realist conceptions of perceptual consciousness. Basically, the argument says that perception and hallucination can have the same proximal causes and must thus belong to the same mental kind. I emphasise that this insight gives us good reasons to abandon what we are instinctively driven to believe - namely that perception is directly about the outside physical world. The causal argument essentially highlights that the information that the subject acquires in perceiving a worldly object is always indirect. To put it another way, the argument shows that what we, as perceivers, are immediately aware of, is not an aspect of the world but an aspect of our sensory response to it. A view like this is traditionally known as a Representative Theory of Perception. As a second step, emphasis is put on the task of defending and promoting a new structural version of the Representative Theory of Perception; one that is immune to some major objections that have been standardly levelled at other Representative Theories of Perception. As part of this defence and promotion, I argue that it is only the structural features of perceptual experiences that are fit to represent the empirical world. This line of thought is backed up by a detailed study of the intriguing phenomenon of synaesthesia. More precisely, I concentrate on empirical cases of synaesthetic experiences and argue that some of them provide support for a structural approach to perception. The general picture that emerges in this dissertation is a new perspective on perceptual consciousness that is structural through and through.
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O estudo teve por objectivo fazer a caracterização dos atributos de qualidade de duas variedades (Solo e Local) de papaia produzida em Santiago, Cabo Verde, e definir os atributos que os distribuidores procuram. Foram realizadas avaliações físico-químicas, sensorial e um estudo de mercado. Os parâmetros avaliados foram o peso, cor interior e exterior, textura, espessura da polpa, pH, acidez titulável, SST, fez-se avaliação sensorial a aplicação de um questionário aos importadores de papaia. Os parâmetros SST, Acidez, pH e peso variam significativamente com as variedades, sendo as papaias da variedade Local mais pesadas. A textura varia em função dos graus de maturação, a firmeza apresenta uma diminuição ao longo do amadurecimento, na deformação percebe-se um decréscimo com avançar da maturação, nos parâmetros de cor interna e externa as diferenças encontram-se na interacção entre Variedade e Estado de maturação. A variedade Solo foi mais valorizada na avaliação sensorial assim como no preço, certificação/selo qualidade e doçura pelos distribuidores.
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Behavioral and brain responses to identical stimuli can vary with experimental and task parameters, including the context of stimulus presentation or attention. More surprisingly, computational models suggest that noise-related random fluctuations in brain responses to stimuli would alone be sufficient to engender perceptual differences between physically identical stimuli. In two experiments combining psychophysics and EEG in healthy humans, we investigated brain mechanisms whereby identical stimuli are (erroneously) perceived as different (higher vs lower in pitch or longer vs shorter in duration) in the absence of any change in the experimental context. Even though, as expected, participants' percepts to identical stimuli varied randomly, a classification algorithm based on a mixture of Gaussians model (GMM) showed that there was sufficient information in single-trial EEG to reliably predict participants' judgments of the stimulus dimension. By contrasting electrical neuroimaging analyses of auditory evoked potentials (AEPs) to the identical stimuli as a function of participants' percepts, we identified the precise timing and neural correlates (strength vs topographic modulations) as well as intracranial sources of these erroneous perceptions. In both experiments, AEP differences first occurred ∼100 ms after stimulus onset and were the result of topographic modulations following from changes in the configuration of active brain networks. Source estimations localized the origin of variations in perceived pitch of identical stimuli within right temporal and left frontal areas and of variations in perceived duration within right temporoparietal areas. We discuss our results in terms of providing neurophysiologic evidence for the contribution of random fluctuations in brain activity to conscious perception.
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BACKGROUND: Interventions have been developed to reduce overestimations of substance use among others, especially for alcohol and among students. Nevertheless, there is a lack of knowledge on misperceptions of use for substances other than alcohol. We studied the prevalence of misperceptions of use for tobacco, cannabis, and alcohol and whether the perception of tobacco, cannabis, and alcohol use by others is associated with one's own use. METHODS: Participants (n=5216) in a cohort study from a census of 20-year-old men (N=11,819) estimated the prevalence of tobacco and cannabis use among peers of the same age and sex and the percentage of their peers drinking more alcohol than they did. Using the census data, we determined whether participants overestimated, accurately estimated, or underestimated substance use by others. Regression models were used to compare substance use by those who overestimated or underestimated peer substance with those who accurately estimated peer use. Other variables included in the analyses were the presence of close friends with alcohol or other drug problems and family history of substance use. RESULTS: Tobacco use by others was overestimated by 46.1% and accurately estimated by 37.3% of participants. Cannabis use by others was overestimated by 21.8% and accurately estimated by 31.6% of participants. Alcohol use by others was overestimated by more than half (53.4%) of participants and accurately estimated by 31.0%. In multivariable models, compared with participants who accurately estimated tobacco use by others, those who overestimated it reported smoking more cigarettes per week (incidence rate ratio [IRR] [95% CI], 1.17 [range, 1.05, 1.32]). There was no difference in the number of cigarettes smoked per week between those underestimating and those accurately estimating tobacco use by others (IRR [95% CI], 0.99 [range, 0.84, 1.17]). Compared with participants accurately estimating cannabis use by others, those who overestimated it reported more days of cannabis use per month (IRR [95% CI], 1.43 [range, 1.21, 1.70]), whereas those who underestimated it reported fewer days of cannabis use per month (IRR [95% CI], 0.62 [range, 0.23, 0.75]). Compared with participants accurately estimating alcohol use by others, those who overestimated it reported consuming more drinks per week (IRR [95% CI], 1.57 [range, 1.43, 1.72]), whereas those who underestimated it reported consuming fewer drinks per week (IRR [95% CI], 0.41 [range, 0.34, 0.50]). CONCLUSIONS: Perceptions of substance use by others are associated with one's own use. In particular, overestimating use by others is frequent among young men and is associated with one's own greater consumption. This association is independent of the substance use environment, indicating that, even in the case of proximity to a heavy-usage group, perception of use by others may influence one's own use. If preventive interventions are to be based on normative feedback, and their aim is to reduce overestimations of use by others, then the prevalence of overestimation indicates that they may be of benefit to roughly half the population; or, in the case of cannabis, to as few as 20%. Such interventions should take into account differing strengths of association across substances.
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Evidence-based medicine has enabled to approach disease in a more rational and scientific way. Clinical research has identified behaviours and risk factors that could cause disease often "silent" at the beginning, such as diabetes. Despite the clear impact of these evidences on public health, it seems that the individual risk perception level remains weak. To mention as well, the health professionals very often have a different views, which makes it difficult to communicate the risk with patients. In this article we describe the principles of risk perception, the diabetes related risk perception concerning cardiovascular complications, and suggest some practical strategies and tools which could improve risk communication in the everyday practice.