Fig. 3: Similarity-based word arrangement task (SWAT) and behavioral representational similarity analysis imputation approach.

A On each SWAT trial, a set of 60 words initially appeared in a random order in a box on the left side of the screen. Words would move to the main canvas when clicked, and once there could be dragged to a chosen location. Participants were instructed to place words that were more similar closer together but not given any rules for how to judge similarity. Participants could move words around until they were satisfied with their final arrangement. Words on the canvas in this figure are enlarged for readability. The assessment included four SWAT trials, and each word occurred on two of these trials. B Crucially, words from to-be-learned pairs never co-occurred on any SWAT trial to avoid potential contamination of their perceived relatedness, so the similarity of these pairs was imputed (see Methods). Euclidean distance was calculated for each pair of words as a proxy for dissimilarity and later converted to similarity for ease of interpretation. Lighter colors reflect pairs that are closer in semantic space, darker colors reflect pairs that were further away in semantic space. Note that the vectors displayed in this figure only show 40 values; the true imputation process would include all 120 potential similarity values.