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Visual Search Task (visual + search_task)
Selected AbstractsSelective attention in anxiety: Distraction and enhancement in visual searchDEPRESSION AND ANXIETY, Issue 1 2003Mike Rinck Abstract According to cognitive models of anxiety, anxiety patients exhibit an attentional bias towards threat, manifested as greater distractibility by threat stimuli and enhanced detection of them. Both phenomena were studied in two experiments, using a modified visual search task, in which participants were asked to find single target words (GAD-related, speech-related, neutral, or positive) hidden in matrices made up of distractor words (also GAD-related, speech-related, neutral, or positive). Generalized anxiety disorder (GAD) patients, social phobia (SP) patients afraid of giving speeches, and healthy controls participated in the visual search task. GAD patients were slowed by GAD-related distractor words but did not show statistically reliable evidence of enhanced detection of GAD-related target words. SP patients showed neither distraction nor enhancement effects. These results extend previous findings of attentional biases observed with other experimental paradigms. Depression and Anxiety 18:18,28, 2003. © 2003 Wiley-Liss, Inc. [source] Brain,behavior correlation in children depends on the neurocognitive networkHUMAN BRAIN MAPPING, Issue 2 2004James R. Booth We examined brain,behavior correlations in 12 children (age range 9.3 to 11.7 years) during a selective attention task that required the visual search of a conjunction of features and during a response inhibition task that required the inhibition of a pre-potent response during "no-go" blocks. We found that the association between performance in these tasks and brain activation as measured by functional magnetic resonance imaging (fMRI) depended on the neurocognitive network. Specifically, better performance during the no-go task was associated with greater activation in the response inhibition network including the prefrontal cortex and basal ganglia. In contrast, better performance during the visual search task was associated with less activation in the selective attention network including superior parietal lobule and lateral premotor cortex. These results show that the relation of performance to the magnitude of neural activation is complex and may display differential relationships based on the cognitive domain, anatomical region, and perhaps also developmental stage. Hum Brain Mapping 23:99,108, 2004. © 2004 Wiley-Liss, Inc. [source] Development of letter position processing: effects of age and orthographic transparencyJOURNAL OF RESEARCH IN READING, Issue 2 2009Maria Ktori This study investigated the relative extent to which developing readers (6- and 9-year-olds) of English (deep) or Greek (transparent) orthography exhibit serial and exterior letter effects in letter position encoding. Participants were given a visual search task that required detection of a pre-specified target letter within a random five-letter string. Stimuli comprised letters either specific to English or Greek, or shared by both orthographies. For native letters, all readers showed significant initial-letter facilitation. In contrast, final-letter facilitation was shown only by English children. Furthermore, Greek 9-year-olds showed significantly more left-to-right facilitation than English 9-year-olds. These results suggest that letter position encoding is adaptive to the nature of the orthography acquired during reading development. [source] The dynamics of cardiac defense: From attention to actionPSYCHOPHYSIOLOGY, Issue 5 2010Isabel Ramírez Abstract The attentional and motivational significance of cardiac defense is examined in two studies. In Study 1, cardiac defense was evoked by an intense acoustic stimulus in the context of either a visual search or a memory search task using letters as stimuli. Results showed a potentiation of the long latency acceleration of cardiac defense in the visual search task. In Study 2, participants performed the same visual search task using pleasant, neutral, and unpleasant pictures as stimuli. Results showed a further potentiation of the long latency acceleration of cardiac defense when the visual search task was performed with unpleasant, compared to pleasant or neutral pictures. These results indicate that cardiac defense has both attentional and motivational contributions, where the attentional significance is related to increased sensory processing, whereas the motivational significance is associated with preparation for active defense. [source] Does focused endogenous attention prevent attentional capture in pop-out visual search?PSYCHOPHYSIOLOGY, Issue 4 2009Ellen Seiss Abstract To investigate whether salient visual singletons capture attention when they appear outside the current endogenous attentional focus, we measured the N2pc component as a marker of attentional capture in a visual search task where target or nontarget singletons were presented at locations previously cued as task-relevant, or in the uncued irrelevant hemifield. In two experiments, targets were either defined by color or by a combination of color and shape. The N2pc was elicited both for attended singletons and for singletons on the uncued side, demonstrating that focused endogenous attention cannot prevent attentional capture by salient unattended visual events. However, N2pc amplitudes were larger for attended and unattended singletons that shared features with the current target, suggesting that top-down task sets modulate the capacity of visual singletons to capture attention both within and outside the current attentional focus. [source] Analyzing user interaction with the ViewFinder video retrieval systemJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 2 2010Dan Albertson This study investigates interactive video retrieval. The basis for this study is that user- and search task-centric research in video information retrieval can assist efforts for developing effective user interfaces and help complement the existing corpus of video retrieval research by providing evidence for the benefits of evaluating systems using such an approach. Accordingly, the results were collected and analyzed from the perspective of certain users and search tasks (i.e., information needs). The methodology of this study employed specially designed interactive search experiments to examine a number of different factors in a video retrieval context, including those that correspond to search tasks of a particular domain, interface features and functions, system effectiveness, and user interactions. The results indicated that the use and effectiveness of certain interface features and functions were dependent on the type of search task, while others were more consistent across the full experiment. Also included is a review of prior research pertaining to visual search tasks, systems development, and user interaction. ViewFinder, the prototype system used to carry out the interactive search experiments of this study, is fully described. [source] Bias in attending to emotional facial expressions: Anxiety and visual search efficiencyAPPLIED COGNITIVE PSYCHOLOGY, Issue 3 2010Eriko Matsumoto There has been much controversy around the relationship between anxiety and attentional processing of threat-related information. The purpose of this study was to examine how threatening facial expressions affect attentional processing, according to the level of trait anxiety. Through visual search tasks, two different components of attentional bias to threat were investigated: engagement and disengagement of attention from an angry face. Two main results were found. First, reaction times (RTs) were slower in detecting the absence of a discrepant face in the all angry-display conditions rather than other expression conditions; however, there was no difference between anxiety groups. Second, the difference in search efficiency for the angry versus happy target was significant within the high-anxiety group but not within the low-anxiety group. The results suggest that the detection process for angry faces is more efficient for highly anxious people. On the other hand, the time to disengage attention from angry faces was not associated with anxiety level. Copyright © 2010 John Wiley & Sons, Ltd. [source] | ||||||||||