Functional roles of memory for feature-location binding in event perception: Investigation with spatiotemporal visual search

Abstract

In a dynamic environment full of degraded or missing perceptual information, memory might facilitate or even substitute efficiently for perception. We tested this idea with a “spatiotemporal search” task that required participants to search for a target defined by a binding of two features across a single object, across two points in time. Eight coloured bars moved horizontally until they became partially occluded behind squares. Before the tail of the bar becomes occluded, the head of the bar reemerged with a possibly different colour. Observers were precued a subset of the bars, and judged the presence of a colour changing target among the precued set. A series of three experiments revealed that memory can substitute for perception only for one object, and that the preview of colour-location binding does not facilitate perceptual processing. Cueing location and object features do not have additive effects. Binding memory may have highly limited capacity in substitution and facilitation of perception.

Keywords:

• Binding
• Visual working memory
• Visual search
• Capacity limit
• Spatiotemporal

Acknowledgements

I thank Steve Franconeri, and two anonymous reviewers for helpful comments on the earlier draft of the paper. This work was partially supported from Grants-in-Aid (#13610084, #14019053, and #19500226) from JMEXT, the Global COE Program “Revitalizing Education for Dynamic Hearts and Minds”, from JMEXT, and PRESTO from JST.

Notes

¹A follow-up experiment (N=7) replicated Experiment 3 with two reappearance durations (200 ms and 680 ms), and without the perception-plus-memory condition to eliminate strategic uncertainty. To evaluate overwriting effect, a long-occluder condition, where objects’ tail was occluded at the time of head reappearance, was added. Using accuracy increment from 200 ms to 680 ms conditions as an index, both memory (M=0.185) and long-occluder (M=0.208) conditions showed significantly smaller increment relative to the perception condition (M=0.357) with Tukey's HSD test (both p<.005), suggesting that neither overwriting nor strategic uncertainty was primary cause of the memory cost.