1,721,020 research outputs found
Ocular and neuronal responses to visual stimuli during free exploration of naturalistic videos in rhesus macaques
No full textUnder natural conditions, eyes are free to explore the visual scene, and both transient pupil dilations and saccadic movements can be influenced by the salience of visual stimuli. Despite its significance, these aspects of visual exploration and the related neural correlates remain poorly investigated. Here we tackle this topic by studying the patterns of ocular behavior of a macaque monkey watching a naturalistic video while recording the neuronal activity from three areas of the frontal cortex (Prefrontal, Premotor Dorsal rostral, and Premotor Dorsal caudal). Different scenes were assigned to four different categories of stimuli depending on the occurrence in the video, which included natural scenes, conspecifics, non-conspecific predators, and non-conspecific harmless animals. Analysis of pupillometry revealed greater dilation when the monkey was exposed to conspecifics compared to both natural landscapes and non-conspecifics, with a further increase in size if non-conspecifics were predator animals. The frequency of saccades did not differ significantly between the other categories. Notably, neuronal activity in each brain area was higher for scenes eliciting higher pupil dilatation, suggesting their possible involvement in processing stimulus saliency
Dynamic pupil responses and neuronal correlates during free view exploration in one rhesus macaque
No full textThe physiological correlates of the salience of specific stimuli have primarily been investigated by exposing subjects (or trained primates) to maintain fixation on static stimuli. Pupil dilation emerges as a crucial variable in this context; indeed, transient pupil dilations can be influenced by the salience of visual stimuli. In natural conditions, however, eyes are free to explore the visual scene, and ocular movement is directed by stimuli that appear within the scene. Despite its significance, this aspect of visual exploration remains poorly understood, with limited knowledge about pupil variations during free visual exploration and the underlying neural activity.
To explore these aspects, single unit recording of neurons in three areas (premotor dorsal rostral, premotor dorsal caudal, dorsolateral prefrontal cortex) and ocular behavior measurements were conducted in one rhesus macaque during free exploration of videos. Different categories of stimuli were identified within the video, including natural scenes, conspecifics, and threatening non-conspecific animals. Statistical tests were performed to identify if the pupil dilatation and the neuronal activity differ between the different categories of stimuli.
Pupillometry revealed greater dilation when the monkey was exposed to conspecifics compared to natural landscapes, and to dangerous non-conspecifics, as jaguars, compared to harmless ones, as deer. Of interest, neuronal activity in the studied cortical areas was higher under conditions where pupil dilation was greater.
The results suggest that both pupil dilation and neuronal activity in the examined areas of the frontal cortex reflect the degree of scene salience
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
Variations 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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