Visual cues as perceptual load: Cues can create additional cognitive demands in interactive visualizations despite being perceived as helpful

Perceptually rich visualizations are known to pose cognitive demands on learners. Cognitive load theory suggests that design choices can mitigate negative effects on learning performance. We aim to evaluate whether cueing is able to reduce the cognitive demands of a parallax effect induced by constrained interactivity in learning with perceptually rich visualizations. 191 university students were included in the final sample of the experiment. Participants were randomly assigned to learn with a perceptually rich anatomical visualization in one of four versions resulting from the factors constrained interactivity (static vs. interactive parallax effect) and visual boundary cues (without vs. with cues). The constrained interactivity allowed participants to slightly rotate an anatomical model by creating a visual parallax effect. Subjective cognitive load during learning was assessed using a survey instrument. Participants completed a picture-based and a text-based retention test. Contrary to the notion that cues help learners facing perceptually rich task, we found that cues only benefit learning with the static visualization. As indicated by an interaction effect, cueing lowered retention performance in the constrained interactive condition. Germane cognitive load ratings suggest that participants recognized the cues as helpful in the interactive parallax effect condition while preferring the uncued variant in the static condition. The cognitive demands of minimally interactive perceptually rich visualizations cannot simply be reduced by inserting boundary cues. Instead, visual cues may even add to the perceptual richness of visualizations featuring subtle forms of interactivity. It is suggested that the perceptual demands of a slightly adjustable visualization that was augmented by boundary cues may have been too high. This finding is of great importance for the design of perceptually rich visualizations.