Researcher(s)
- Kallie Sweetman, Psychology, University of Delaware
Faculty Mentor(s)
- Tim Vickery, Psychological and Brain Sciences, University of Delaware
- Helene Intraub, Psychological and Brain Sciences, University of Delaware
Abstract
Memories include more details than were actually present. Boundary extension occurs when one views a scene, including a close-up view of an object, and then, while remembering the scene, they extrapolate beyond the physical boundaries of the original image. This experiment investigates if a classifier reveals the neural basis of boundary extension. Using functional magnetic resonance imaging (fMRI), we trained a classifier to discriminate between brain patterns that were evoked by wide-view scenes versus close-view scenes. The classifier was applied to imagery of scenes, that were studied in either close- or wide-view, to determine where in the brain boundary extension occurs. We reasoned that boundary extension would result in misclassifying close-view memories as wide-view, whereas wide-view images would be classified correctly. In parietal, anterior occipital, and parahippocampal regions, we discovered a misclassification of close-view memories as wide-view, while in the early visual areas, we found an opposite result of wide-view memories misclassified as close-view. Investigating boundary extension through fMRI provides a novel tool to study this phenomenon differently from a behavioral approach.