1,720,955 research outputs found
A Neurophysiological Investigation of Listening Effort in Normal Hearing Adults Using fNIRS and Pupillometry
Get PDFReal-world conversations are often accompanied by some sort of interference that challenges the clarity of the speaker’s message, causing listeners to exert more effort to understand speech. Previous research has demonstrated that when listening to speech becomes difficult, various regions of the brain are recruited beyond those which engage during optimal listening conditions. However, the neural correlates that underly listening effort are not fully understood. Importantly, the pupillary response can be used to index listening effort, such that pupil size increases with increasing cognitive demand. I proposed that pupillometry can be used to characterize the cortical response, such that changes in pupil size would be associated with neural activation that directly relates to effortful processing. The primary goal of this study was to investigate the physiological mechanisms underlying recognition of realistic cochlear implant (CI) speech simulations (i.e., vocoded speech) and examine how effort might be alleviated with access to semantic information. To achieve this, I implemented a speech recognition task and manipulated the semantic content of the sentence (Predictability), spectral degradation (Speech Quality), and the way participants reported their response (Task Mode). Concurrent measurements of speech recognition, pupillary responses, and cortical activation via functional near infrared spectroscopy (fNIRS) were recorded from 41 normal hearing (NH) adults. As expected, challenging vocoded speech resulted in larger pupil sizes than did non-vocoded speech, and use of semantic information reduced listening effort. Interestingly, the largest exertion of listening effort was produced after the sentence presentation ended. Neural data revealed Predictability effects in frontal, temporal, and parietal cortices, such that activation in frontal regions responded to higher-level semantic representations of speech, and posterior brain regions were more sensitive to Task Mode which modulated the cortical mechanisms used to resolve Predictability. Positive correlations between the strength of the neural response and peak pupil response were observed in the Middle Frontal Gyrus (MFG) and Inferior Parietal Cortex (IPC), revealing cortical regions related to listening effort. Surprisingly, pupil size just prior to the sentence onset positively predicted individual speech recognition score, suggesting that the degree to which participants were engaged (or prepared) at the start of the trial predicted their overall speech recognition performance. On the other hand, pupil size right after sentence offset was negatively associated individual capacity to exploit semantic information, suggesting that listeners with smaller improvement from Low- to High-Predictability conditions had engaged more effort after the sentence was presented. Overall, the findings presented here indicate that the MFG and IPC carry out cortical mechanisms related to effortful processing, and listeners with a stronger MFG response were more impacted by the degraded listening conditions as they exhibited more effort (larger pupil size) and lower benefit in performance from semantic information. Therefore, it appears that the effect of listening effort on communication (i.e., speech recognition score and semantic capacity) is determined by the individual physiological response of the listener
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Differences in Group Value Priorities and Their Impact on Political Candidate Support:A Consideration of Sex, Party, and Race
No full textAuthor-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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