ADULT PERCEPTION AND CONCEPTIONS OF SINGLE AND TWO FORCE INTERACTIONS

Abstract

Since the first studies on perceptual causality, there has been a debate about whether or not causality can be directly perceived or if reports of causality are the products of higher level memory and cognition. This dissertation directly tests the relationship between causality, animacy, and higher level cognition for events that entail one and two force interactions. Perceptual causality and animacy were reported in a recognition task where participants viewed animations of single and two force events. The events simulated: interactions that obeyed the laws of physics, interactions that reflected high frequency alternate conceptions found through a pilot study, and a parametrically varied set of angular deviations from the motions in the set that obeyed physics. Results showed that reports of perceptual causality and perceptual animacy were highly negatively correlated. Solutions that likely appeared physically plausible—such as correct physics paths and high frequency alternate conceptions—were rated as high in causality and low in animacy and highly implausible solutions—such as motions 180 degrees from the correct physics path—were rated as low in causality and high in animacy. Higher level cognition was tested through a production task where participants were asked to predict the path they believed a ball would take when acted upon by one or two forces. This task allowed novices to report their conceptions of single and two force interactions. In addition to paths that closely resembled the physically correct path, people also frequently produced paths that had inaccurate angles, that were curved, or that appeared to be determined by the larger or more recent of the two forces. The combined results suggest that higher level cognition played a role in the experience of causality and animacy in the animations, with animation paths similar to those generated during the production task rated higher in naturalness and lower in animacy than other types of paths, but that this effect was dependent on the complexity of the force interaction. Recognition task results for single force and two equal forces facing each other were not predicted by the type of path generated during the production task, but production task results did predict recognition task ratings for all other force relations tested. Different aspects of the data support each of the two sides of the debate; causality may be directly perceived in some, but not all, situations.