Figure 3.

Stimulus dissimilarities. A, Distance matrix for all natural movies used in the experiment (in SD units, see Materials and Methods, Stimuli). Colored boxes highlight target (T) and natural distractor (D) combinations per stimulus set. Black circles indicate distances shorter than one (i.e., the criterion for target–distractor match). B, All stimuli in 2D space after principal component analysis on the distance matrix from A. Full markers indicate targets and empty circles indicate distractors (color codes correspond to those in A). Black markers indicate distractors that are shared by two target movies. Variance explained by these first two principal components is 83.6%. C, Parallel coordinates plot showing bee-swarm plots of individual stimuli per dimension and the centroids (averages) of each stimulus set for targets (continuous lines) and distractors (dashed lines) separately in the standardized 6D stimulus space (color codes correspond to those in A).