1,720,966 research outputs found
Olphactory Cognition and Conditioning Event Related Potentials towards Innovative Applications in Cognitive Neuroscience
Full text linkThe perception of an odour is a two-step process. First, there is a physiological process, i.e. the detection of chemical stimuli (odorous molecules) by olfactory receptors in the olfactory epithelium. Next, there is a neurologic process; olfactory neurons transduce receptors activation into neuronal electrical signals travelling along the olfactory nerve to olfactory bulb and finally, they are processed by higher cortical areas of the human brain where odour encoding and perception occur. Because of this, olfaction is a complex primal sense highly associated with attraction, mood, detection of danger and odours have the power to evoke distant memories and boost self-confidence. A lot of knowledge on olfaction has to be still get mainly regarding its relationship with other sensory stimuli as audio, visual, taste [1]. Odour recognition memory is slightly influenced by the length of retention intervals. This was observed for short intervals (few minutes) as well as longer retention period (over a year too)[2]. One approach to understanding the olfaction links to other senses is to monitor and analyse human brain activity during odours perception. By measuring event-related potentials (ERPs) by electroencephalography, it’s possible to measure the electrophysiological response of brain to a specific event, i.e. in this case the presentation of olfactory stimuli [3,4]. Aim of this study is understanding how the olfactory system, which involves and activates the limbic system, can modulate a perception on emotional face recognition. Through these results we aim to investigate and to implement innovative applications of cognitive neuroscience in order to improve basic knowledge as well as to develop novel devices for enhancing synesthetic experiences with olfactory stimuli.
Method: We arrange an experiment of olfactive conditioned evoked potentials by analysing Event Related Potential (ERP) of 7 volunteers during perception of 2 odour stimuli: pleasant (rose, 2-phenyl ethanol C2H4O2) and unpleasant (acid, Acetic Acid C8H10O). Specifically, we have proposed a paradigm of operant conditioning in which the three types of odours were conditioned on images of neuter face expression [5], by a NimStim Face Stimulus Set [6], for the duration of 5 minutes to task learning, repeated for three times. Subsequently, the subject had to perform a test Face detection, implemented through NimStim Set, for a period of 10 minutes task, during a Emo No Go Paradigm Presented with E-Prime Presentation. The subject had to press a pc key during a recognition task of emotional neuter face expression in a presentation of randomized emotional expressions (fear, neuter and happy).
For the odorous stimuli in the experiment, pure chemical compounds were diluted in distilled water. A dilution ratio (1:4) was suitably consider in order to realise easily perceptible, but not unpleasant, odours; the odorants and their concentration used in the test are listed in table 1 together with their odour sensory description. In addition, the distilled water was used a control for inducing an odourless stimulus. The odorous solutions (5 ml) were put into 20 ml glass vials sealed with septum till the exposure time to the volunteers.
We can conclude that an unpleasant odour can modulate, in a cross modal way, the perceptions of emotional and neutral face expressions, and it can be general in a very early component (P100) and more specific, in conditioning way, in the attentive component (P300), only for neutral expression
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Spin-coated thin films of different metal phthalocyanines and porphyrin-phthalocyanine blend for optochemical sensors of volatile organic compounds
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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