Abstracts - Earli

versions of a non-idealised Newton’s Cradle animation in six different conditions. Thepresentation sets in these conditions varied in terms of animation speed, set composition, anddisplay order. Participants then completed physical simulation tasks to demonstrate the device’sdynamics and make related predictions. Extraction of perceptually subtle but task-relevant microlevel information was superior for multiple successive exposures to slow presentation speedversions whereas in conditions with a corresponding emphasis on normal speed presentation,extraction of information tended to be confined to the macro level. There was evidence that thesepatterns of extraction influenced the nature of the mental models used for subsequent predictions.The findings suggest that manipulation of an animation’s temporal characteristics can be morebeneficial to learning than a behaviourally realistic presentation of complex dynamic subjectmatter. Such manipulations appear to have potential for supporting learner extraction of lowsalience, high thematic relevance dynamic information that parallels the support provided by thevisuospatial manipulations traditionally used to improve learner processing of static explanatorygraphics.Building dynamic mental models from animation: effect of user control on exploration behavioursMireille Betrancourt, Tecfa, University of Geneva, SwitzerlandCyril Rebetez, Tecfa, University of Geneva, SwitzerlandThough animation seems particularly adequate to convey explanation of dynamic systems, theliterature reports many cases in which animation did not facilitate learning. The currentexplanation is that novices failed to adequately process the graphic dynamic information and tobuild a mental model from it. It is assumed that giving control over the pace of the animationenables the progressive processing of multimedia information and facilitates the construction ofthe mental model. We carried out an experimental study in which learners were given either nocontrol or high control on playing a series of animated sequences accompanied with textinformation. We found no significant effect on learning performance. However, we observedvarious behaviours in studying the multimedia material in both conditions. The results comfortedthe assumption that giving learners control over the pace of the animation can differently affectlearning performance depending on their actual use of the control device.Reasoning with interactive visualizations: The importance of individual differences among usersMadeleine Keehner, Curtin University of Technology, Perth, AustraliaMary Hegarty, University of California Santa Barbara, USACheryl Cohen, Universitay of California Santa Barbara, USAPeter Khooshabeh, University of California Santa Barbara, USAIn three experiments we examined interactivity and spatial ability in a task requiring participants toinfer and draw cross sections through a virtual 3-D object with a complex internal structure. Wemanipulated whether participants could interactively control a computerized 3-D visualization ofthe object while performing the task. We also digitally recorded and analyzed patterns ofinteractive behavior among those who were given active control over the visualization. InExperiment 1, interactivity produced better performance than passive viewing of the objectcontinuously rotating. However, this advantage disappeared in Experiment 2 when we equalizedthe visual information available in the two conditions using a yoked-pairs design. In Experiments2 and 3, we observed large individual differences in how participants manipulated thevisualization, and found that these were systematically related to performance on the task. InExperiment 3, non-interactive participants who watched pre-programmed optimal movements ofthe display (based on the best-performing interactive participants’ manipulations) performed as– 190 –