13:30 - 15:00
Mon-A6-Talk II-
Mon-Talk II-
Room: A6
Chair/s:
Simon Merz
Spatial changes of an object over time are usually perceived as motion. Over the years, various perceptual errors have been identified for dynamic, moving objects. These include, but are not limited to, spatial over- or underestimation of the initial or final position (e.g. Fröhlich Effect, Onset-Repulsion Effect, Representational-Momentum Effect, Offset-Repulsion Effect), spatio-temporal discrepancies between moving and stationary objects (Flash-Lag Effect, Flash-Drag Effect) or the interaction between spatial and temporal properties of a dynamic display (e.g. Kappa Effect, Tau Effect). Given the vast amount of different perceptual errors reported over the decades, many theoretical explanations have been proposed. With the common goal of understanding spatio-temporal perception of dynamic objects, the symposium aims to bring together researchers working on the different perceptual biases to enable cross-paradigm perspectives and discussion. The speakers will present experimental work using different experimental procedures, analytical approaches and theoretical background to show current developments in the field, with the final talk in the session allowing general, talk overarching discussions about human spatio-temporal perception and the possible mechanisms underlying these processes.
Localization Errors in Context
Mon-A6-Talk II-02
Presented by: Ian M. Thornton
Ian M. Thornton
Department of Cognitive Science, University of Malta
In laboratory experiments, it has often been reported that observers tend to mislocalize the position of moving objects. In most such studies, the target object in question is relatively simple (e.g., a single dot or a line), and its local motion is presented in isolation, devoid of the usual global context present when things move in the world around us. Is global context then irrelevant for understanding how we perceive the position of moving objects? Here I will argue that it is not, for at least two reasons. First, global scene context may typically provide additional reference information that can anchor/improve local estimates of object motion, helping to reduce localization errors. Second, integration of local motion components within an object or scene may sometimes dramatically alter our overall, global percept (e.g., biological motion, aperture-effect). We might expect such global dynamics to also modulate patterns of localization. Here I will provide evidence from two recent representational momentum (Freyd & Finke, 1984) studies that specifically address this second aspect of context.
Keywords: Motion, localisation, context, representational momentum