1,721,058 research outputs found
Integrating nonspatial, nontemporal multisensory information in action-based perception
No full textThe study of multisensory perception has traditionally emphasized the integration of temporal and spatial aspects of events in nonaction settings. We adopted an action-based paradigm to investigate the factors affecting how nonspatial and nontemporal multisensory information is integrated. On a trial, participants struck a virtual object with a constant velocity and received feedback on correctness. When a performance criterion was reached, feedback was eliminated, the properties of the stimulus were changed, and the effects on striking velocity and performance were measured.
In Experiment 1, we studied the effects of the congruence of multisensory information and of a participant's expertise in the task. We studied a unimodal or a multisensory audio-haptic display in which the haptic and sound hardness of the object were manipulated. In multisensory trials, the audio-haptic changes could be congruent (e.g., both increased in hardness) or incongruent. We recruited participants with different levels of expertise with the task: percussionists, nonpercussionist musicians and nonmusicians. Overall, striking velocity decreased with an increase in both haptic and sound hardness. The level of expertise influenced the effects of haptic, but not of sound, hardness, where only percussionists struck harder haptic objects faster. For all participants, striking velocity in the multisensory trials was most strongly affected by changes in haptic hardness. Further, the effects of hardness were much more similar across participants in the auditory than in the haptic modality. Multisensory congruence modulated the effects of sound but not haptic hardness: whereas in congruent trials the effects of audio hardness were the same as in the unimodal condition, audio hardness was behaviorally irrelevant when it varied in opposition to haptic hardness. Overall, performance did not improve from the unimodal to the multisensory context. Only for nonmusicians, performance was significantly better in the audio-only condition. In summary, the effects of the least relevant modality, audition, were more similar across individuals, were independent of expertise and were modulated by multisensory congruence. On the contrary, the effects of the primary modality, haptics, varied more across individuals, were influenced by expertise, and were independent of multisensory congruence.
In Experiment 2, we assessed the behavioral relevance of a visual property of the display. Nonmusicians were presented with either a visual or a visual-audio-haptic stimulus. We manipulated the speed of the visual striking object, and, in multisensory congruent trials, also the sound and haptic hardness. Participants wore a head mounted display. Striking velocity decreased for increasing haptic and sound hardness, and for decreasing speeds of the striking object. Future investigations will extend the results of Experiment 1 to visual-audio-haptic contexts
Multisensory integration in percussion performance [CD-ROM]
No full textWe investigated how auditory and haptic information about the hardness of objects is integrated for the purpose of controlling the velocity with which we strike an object. Our experimental manipulations and data analyses considered a variety of factors that should be integrated in a theory of multisensory perception: expertise of the perceiver; context (unimodal vs. multimodal); between-modalities congruence; between-participants agreement in sensory weighting; performance.
On a trial, participants struck a virtual object with a constant velocity and received feedback on correctness. When the performance criterion was reached, feedback was eliminated, the auditory and/or haptic hardness of the struck object were changed, and the effects on subsequent striking velocity and performance were measured. In unimodal trials only the haptic or auditory display was presented. In multisensory trials, the audio-haptic changes could be congruent (e.g., both increased in hardness) or incongruent. We recruited participants with different levels of expertise with the task: percussionists, nonpercussionist musicians and nonmusicians.
For both modalities, striking velocity increased with decreasing hardness, and vice versa. With the vast majority of participants, changes in haptic hardness were perceptually more relevant because they influenced striking velocity to a greater degree than changes in auditory hardness. The perceptual weighting of auditory information was robust to context variations (unimodal vs. multimodal), independent of expertise, uniform across participants and modulated by audio-haptic congruence. The perceptual weighting of haptic information was modulated by context and expertise, more varied across participants and robust to changes in audio-haptic congruence. Performance in tracking velocity was more strongly affected by haptic than auditory information, was not at its best in a multisensory context and was independent of information congruence
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
Integration of acoustical information in the perception of impacted sound sources: the role of information accuracy and exploitability
No full textSound sources are perceived by integrating information from multiple acoustical features. The factors influencing the integration of information are largely unknown. We measured how the perceptual weighting of different features varies with the accuracy of information and with a listener’s ability to exploit it. Participants judged the hardness of two objects whose interaction generates an impact sound: a hammer and a sounding object. In a first discrimination experiment, trained listeners focused on the most accurate information, although with greater difficulty when perceiving the hammer. We inferred a limited exploitability for the most accurate hammer-hardness information. In a second rating experiment, listeners focused on the most accurate information only when estimating sounding-object hardness. In a third rating experiment, we synthesized sounds by independently manipulating source properties that covaried in Experiments 1 and 2: sounding-object hardness and impact properties. Sounding-object hardness perception relied on the most accurate acoustical information, whereas impact-properties influenced more strongly hammer hardness perception. Overall, perceptual weight increased with the accuracy of acoustical information, although information that was not easily exploited was perceptually secondary, even if accurate
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
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