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bioRxiv · 10.1101/234609

Visual Continuous Recognition Reveals Widespread Cortical Contributions to Scene Memory

Abstract

Humans have a remarkably high capacity and long duration memory for complex scenes. Previous research documents the neural substrates that allow for efficient categorization of scenes from other complex stimuli like objects and faces, but the spatiotemporal neural dynamics underlying scene memory are less well understood. In the present study, we used high density EEG during a visual continuous recognition task in which new, old, and scrambled scenes consisting of color outdoor photographs were presented at an average rate 0.26 Hz. Old scenes were single repeated presentations occurring within either a short-term ([≤] 20 seconds) or longer-term intervals of between 30 sec and 3 minutes or 4 and 10 minutes. Overall recognition was far above chance, with better performance at short- than longer-term intervals. A group ANOVA found parietal and frontal ERPs discriminated the three scene types as early as 59 ms after stimulus onset. Parietal ERPs were greater for old compared to new scenes by 189 ms, while fronto-temporal ERPs were greater for new compared to old scenes by 194 ms. For old scenes presented within longer-term intervals, parieto-temporal and centro-frontal ERPs were greater by 228 and 355 ms respectively compared to old scenes presented within a short-term interval. Supervised machine learning exhibited above-chance decoding of scene type by 275 ms. Single-subject BOLD-fMRI showed greater activity for old scenes across frontal, parietal, and temporal cortex. These converging findings show that a widespread network including parietal, frontal, and temporal regions supports short- and long-term scene memory.\n\nSignificance StatementThe ability to recognize a scene as novel or familiar is critical for basic cognition. Scene recognition plays an important role in episodic memory because it helps us quickly establish place, a first step in recalling where previous events occurred. Short-term recognition supports our ability to detect changes in the immediate environment, an ability critical to survival. Scene recognition after a longer-term interval is often the essential cue for retrieving autobiographical memories. Previous behavioral studies demonstrate high capacity and long duration scene memory. Neural studies have identified the brain regions that support scene-specific processing. The present study extends this research by filling a gap in understanding how distributed spatiotemporal patterns of neural activity support short- and long-term scene memory.

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BibTeXRIS

Ellmore, T. M., Reichert, C. P., Ng, K., Mei, N.. 2017-12-15. Visual Continuous Recognition Reveals Widespread Cortical Contributions to Scene Memory. https://doi.org/10.1101/234609

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