How Viewers Structure and Describe Animated Thematic Maps: an Event Segmentation Approach Using Free Recall

Abstract Animated thematic maps are a powerful way to communicate how phenomena change over space and time. However, they place substantial cognitive demands on viewers, who must organize continuously unfolding information into meaningful structure. This study examines the role of event segmentation, the cognitive process of partitioning continuous input into discrete events, in the comprehension of dynamic maps. Specifically, it probes how segmentation during perception relates to how viewers later describe animated maps. In two online experiments ( N = 538), participants viewed animated choropleth maps depicting changes in insect population density, segmented the unfolding animation into meaningful units, and then described the map’s development in their own words. Recall responses were analyzed with regard to the spatial structure they reflected and the overlap between viewers. Further, the analyses compared stepwise (discrete) and continuous (smoothly interpolated) animation styles. Across analyses, a consistent pattern emerged: participants whose segmentation was more closely aligned with the group pattern produced descriptions that captured aspects of the map’s underlying structure more consistently. Specifically, their responses grouped regions that shared temporal trajectories and were more similar to those of other participants and structured reference descriptions. Additionally, animation style influenced both segmentation behavior and description patterns. The findings suggest that how viewers segment dynamic maps is linked to how they structure and communicate what they have seen. Methodologically, the study examines how free recall, combined with text-analytic measures, can be used to assess cognitive processing of animated maps in large samples. Given the exploratory nature of the analyses, these results provide a basis for further research questions on segmentation, memory, and map design.