| Reference code: | PT/FB/BL-2006-073.11 |
| Location: | Arquivo PCA - Pasta 22/2006
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Title:
| Implicit object cueing: A study of oculomotor parameters and peripheral vision
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| Publication year: | 2008
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URL:
| Visitante: / http://www.abstractsonline.com/Plan/ViewAbstract.aspx?sKey=8859d545-285d-4e9d-85f7-274d1c7fbf37&cKey=c5dbd828-ffef-4756-8e6a-c1ba585bab1b&mKey=%7bAFEA068D-D012-4520-8E42-10E4D1AF7944%7d
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| Abstract/Results: | ABSTRACT:
Implicit context cueing refers to a top-down mechanism in which visual search is facilitated by learned contextual features. To define the underlying mechanism of this phenomenon, previous studies have analyzed the effect of repeated spatial configurations. Although this paradigm has lead to important insights, it can be argued that it has biased our knowledge about implicit context cueing, since spatial context cueing has the unique characteristic that the location of a target is predictable. That is, the target position is fixed in relation to the spatial configuration. When object cues are used, the mechanism that facilitates search is not so obvious. In the current study we aim to investigate the mechanisms underlying object cueing by studying eye movements and we try to define the role of peripheral vision. A visual search task was used in which participants (n = 16) had to locate a target object (abstract line drawing with an opening) among a number of distractors (closed abstract line drawing). In half of the trials the set of objects presented was repeated (Repeated trials), whereas in the other trials a new set of objects was used (New trials). The location of the objects was randomly defined and the objects in the Repeated and New trials were repeated the same number of times. Eye movements were recorded with an iViewX High-speed Eye-Tracker. Subjects located the target faster in the Repeated trials as compared with New trials (p<0.001), indicating that the sets of objects were memorized and search was facilitated. By analyzing the different oculomotor parameters, we found that faster response times are due to a decrease in the number of saccades (p<0.05) and not due to a difference in the saccade amplitude, intersaccadic fixation duration or time between last saccade and button press. The finding that fewer saccades are made is particularly fascinating, since it suggests that fewer objects had to be foveated in order to recognize the target. A possible explanation for this finding is that objects do not need to be foveated for object identification, suggesting an important role for peripheral vision. In order to verify this hypothesis, we performed a second experiment in which participants performed the same search task, but now had to foveate a fixation cross during the entire experiment. Surprisingly, repeated object information facilitated search even when only peripheral vision was used (p < 0.05), thus confirming an important role for peripheral vision in implicit context cueing. When the results of these two studies are taken together, we can conclude that implicit object cueing facilitates object recognition in peripheral vision leading to a more effective search.
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| Accessibility: | Document does not exist in file
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Language:
| eng
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Author:
| Van Asselen, M.
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Secondary author(s):
| Castelo-Branco, M., Sampaio, J.
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Document type:
| Online abstract
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Number of reproductions:
| 1
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Reference:
| Van Asselen, M.,Castelo-Branco, M., & Sampaio, J. (2008). Implicit object cueing: A study of oculomotor parameters and peripheral vision. Program No. 483.3/RR64. 2008 Neuroscience Meeting Planner. Washington, DC: Society for Neuroscience. Online. |
| Indexed document: | No
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| Keywords: | Implicit contextual cueing / Visual search / Eye movements / Peripheral vision
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