1,720,961 research outputs found
The effect of face patch microstimulation on perception of faces and objects
Get PDFWhat is the range of stimuli encoded by face-selective regions of the brain? We asked how electrical microstimulation of face patches in macaque inferotemporal cortex affects perception of faces and objects. We found that microstimulation strongly distorted face percepts and that this effect depended on precise targeting to the center of face patches. While microstimulation had no effect on the percept of many non-face objects, it did affect the percept of some, including non-face objects whose shape is consistent with a face (for example, apples) as well as somewhat facelike abstract images (for example, cartoon houses). Microstimulation even perturbed the percept of certain objects that did not activate the stimulated face patch at all. Overall, these results indicate that representation of facial identity is localized to face patches, but activity in these patches can also affect perception of face-compatible non-face objects, including objects normally represented in other parts of inferotemporal cortex
Neuronal mechanisms for evaluating the visual scene across eye movements
Get PDFAs a foveate animal, the primate must redirect its gaze with saccadic eye movements to subject different objects to high resolution analysis. Though beneficial in extending the range of visual analysis, the saccade-and-fixate oculomotor strategy poses a problem to the visual system as it performs its analyses. Each saccade results in a whole-field displacement of the visual image across the retina. Nevertheless, we experience a stable visual percept, implying a brain mechanism for visuo-spatial correction. The experiments reported here examine the neural mechanisms underwriting this correction.In the first study, we sought to understand how the frontal eye field (FEF) gains access to information about ipsilateral space. Information about all of space, not just the contralateral hemifield, is a prerequisite for omnidirectional processes such as spatial remapping, a putative mechanism of visual stability. We found that one source of ipsilateral information is the superior colliculus (SC) on the opposite side of the brain. In the second study, we set out to test a major prediction of one theory of visual stability. This theory invokes the function of neurons with shifting receptive fields (RFs) as a mechanism for achieving transaccadic visual stability. Shifting RFs effectively sample the same region of space twice, presaccadically and postsaccadically, and a percept of stability may rely on how well the samples match. This theory has the salient prediction that neurons in areas where shifting RFs are found should be sensitive to changes that occur to stimuli during saccades. We tested this prediction by recording from FEF neurons while monkeys performed a task during which a probe changed along a particular dimension during a saccade. We found that FEF neurons are indeed sensitive to intrasaccadic alterations of visual stimuli. In a third and final study, we sought to bridge the neuron-behavior gap by recording from FEF neurons while monkeys performed a visual stability judgment task that probed their capacity to detect changes occurring during saccades. We found that monkeys are clearly able to discern whether a stimulus is stable or unstable during a saccade and moreover that FEF neural activity is predictive of monkey psychophysical performance
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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