Theses Doctoral

Designing Exploratory Search Systems that Stimulate Memory and Reduce Cognitive Load

Petridis, Savvas Dimitrios

From music fans finding new songs in a genre, graphic designers brainstorming ways to depict a message, and journalists scrutinizing documents for angles, people often conduct exploratory searches to understand complex topics. In contrast to traditional search, which is done to quickly answer simple questions, exploratory search is an iterative learning process that involves understanding an information space in order to find useful pieces of information.

Exploratory search is composed of two, closely-related sub-processes: (1) information foraging, choosing sources and collecting information, and (2) sensemaking, organizing this information into a mental framework. Both of these sub-processes are cognitively taxing and heavily rely on our memory. For information foraging, users need to read long, complex resources and recognize useful pieces of information. For sensemaking, as users encounter more information, it becomes harder to relate new information to their current knowledge.

The spreading activation theory of memory purports that the information we encounter materializes in our working memory, which spreads activation into our long-term memory, enabling us to recall related semantic information to make sense of newly found information. From this theory, this thesis introduces three strategies for creating organizations that better stimulate memory: (1) constructing overviews that are association networks that mimic our memory's structure, (2) incorporating our prior knowledge in these overviews, and (3) providing concrete information to help us make sense of abstract ideas. This thesis demonstrates how to employ these strategies through three exploratory search systems across three domains: (A) SymbolFinder helps graphic designers explore visual symbols for abstract concepts, (B) TastePaths helps music fans explore artists within a genre, and (C) AngleKindling supports journalists explore story angles for a press release. Through this body of work, I demonstrate that by designing exploratory search systems to stimulate our memory, we can make acquiring and making sense of knowledge less cognitively demanding.


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More About This Work

Academic Units
Computer Science
Thesis Advisors
Chilton, Lydia B.
Ph.D., Columbia University
Published Here
November 23, 2022