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Published on: January 23, 2017
Fixating picture boundaries does not eliminate boundary extension: implications for scene representation.
Kristin Michod Gagnier1, Christopher A Dickinson, Helene Intraub
1a Department of Psychology , University of Delaware , Newark , DE , USA.
Quarterly Journal of Experimental Psychology (2006)
|April 4, 2013
Summary
Boundary extension, a memory error where people recall seeing more than presented, persists even with focused eye fixations on scene boundaries. This visual perception phenomenon was not fully overcome by test knowledge or attention.
Area of Science:
- Cognitive Psychology
- Visual Perception
- Memory Studies
Background:
- Boundary extension is a common memory error where observers recall seeing more of a scene than was actually depicted.
- The role of eye fixations, particularly to boundary regions, in mitigating this memory distortion remains unclear.
Purpose of the Study:
- To investigate whether a lack of eye fixations to scene boundaries contributes to boundary extension.
- To examine the effect of foreknowledge about a boundary memory test on visual attention and boundary extension.
Main Methods:
- Participants viewed single-object photographs, some with objects slightly cropped.
- Eye movements were tracked during viewing, and participants later performed boundary ratings or border adjustment tasks.
- One group was informed about the boundary memory test, while the other was not.
Main Results:
- Participants in both informed and uninformed groups exhibited boundary extension.
- Test-informed participants showed increased and earlier fixations to boundary and cropped regions.
- Despite increased attention and test knowledge, boundary extension was only reduced, not eliminated, in the informed group.
Conclusions:
- Boundary extension can occur despite significant attention to boundary regions.
- Foreknowledge of a boundary memory test can reduce, but not eliminate, this memory error.
- The findings challenge purely visual-centric explanations and support multisource models of scene perception.
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