1,720,978 research outputs found
Attention
No full textAttention is the scientific term primarily usedto describe all processes and mechanisms thatgovern the subjective constraints imposed by thehuman organism on the flow and interpretationof external and internal information, and on theorganization and selection of responses, in the serviceof goal-directed behavior. In some cases, attentioncan also be automatically captured bysudden changes in the situation, or by well-trainedstimulus–response tendencie
Effects of task difficulty and invested mental effort on peripheral vasoconstriction
No full textWe conducted four experiments to test the effects of task difficulty and invested mental effort on peripheral vasoconstriction. Finger pulse wave amplitude was recorded from male undergraduatestudents by means of a newly developed finger plethysmographthat measures peripheral arterial tone (PAT) during both rest and cognitive performance. The difference in PAT amplitude between rest and task periods suggests that PAT amplitude reflects changes in sympathetic activity due to task engagement. As the demands of the task increase, PAT amplitude tends to decrease. Our results seem to suggest that peripheral vasoconstriction may be more sensitive to the amount of voluntary effort invested in task performance rather than to the objective task demands
Evaluation of multimodal feedback effects on the time-course of motor learning in multimodal VR platform for rowing training
No full textThis study focused on the benefits of feedback augmentation for multi-session training of a complex motor-cognitive skill of indoor rowing in virtual environment. Specifically, we compared the effectiveness of augmented information feedback provided per training trial either visually, haptically or visual- haptically to the non-augmented condition, where no on-line feedback on task performance was afforded during training sessions. Surprisingly, the non-augmented training group was in general as successful in the long-term learning of a rowing skill as the augmented groups and according to some measures even superior to them. Our results also highlight important differences in the course of learning and skill representation upon different feedback conditions provided during training and may provide useful insights to the optimization for both sport and rehabilitation training protocols in V
Peripheral arterial tone as an on-line measure of load in a simulated flight task
No full textVariations in continuous and discrete flight demands were investigated in a simulated flight mission measuring peripheral arterial tone (PAT) from the tip of the finger. A total of 12 participants performed a computer-simulated agricultural flight task. They were required to fly over a specific lane of asimulated corn field (continuous task) and change lanes in response to flags, which appeared at varying intervals (discrete task). The difficulty of the flight task was manipulated by varying the airplane control (single- vs. dual-axis control), while the difficulty of the discrete task was manipulated by varyingthe amount of lateral change signalled by the flag. PAT amplitude was lower in the difficult level of the continuous task and was further attenuated following the appearance of the flag only when a change in the flight position was required. These results suggest the potential utility of PAT as an on-line measure of the joint continuous and discrete demands of a flight mission
Effects of task difficulty and invested mental effort on peripheral vasoconstriction
No full textWe ran two experiments to investigate whether peripheral arterial tone reflects changes in mental effort. Finger pulse wave amplitude, interpulse interval, and pulse variability in the mid- and high-frequency bands were recorded by means of a newly developed finger plethysmograph during both rest and cognitive performance. Using a modified version of the Sternberg memory task, we selectively manipulated either the difficulty of the task (Experiment 1) or the subjects' level of engagement in the task (Experiment 2). We found a significant difference in finger pulse wave amplitude between rest and task periods, suggesting that the measure reflects changes in sympathetic activity due to task engagement. In addition, our results suggest that reduced pulse wave amplitude, signaling vasoconstriction, occurs when subjects are investing effort
Feedback, Affordances and Accelerators for Training sports in Virtual Environments
No full textThe use of Virtual Environment (VE) for training sports is quite natural when considering strategic or cognitive aspects. Using VE for sensori-motor training is more challenging, in particular with the difficulty of transferring the task learned in the virtual-world to the real. Of special concern for the successful transfer is the adequate combination of training experience protocols and the delivery modes of multimodal feedback. Analyzing feedback in terms of information exchange, this work discusses different feedback combinations and their application to virtual reality training of rowing skills
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
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