IS VISUAL ANTICIPATION OF COLLISION DURING SELF-MOTION RELATED TO PERCEPTUAL STYLE

We have previously shown that during self-motion in car driving situat ions, the perception of another car's trajectory relies both on global visual information such as the optical flow field, and on local visua l information such as the optical motion of the other car and the rela tive optical motion of the other car with respect to fixed elements in the environment. Here, we studied the environmental factors that cont ribute to perceptual judgements in relation to the observer's perceptu al style (visual-field dependence vs, visual-field independence). In a n experiment, observers were presented with visual scenes correspondin g to the curvilinear self-motion of a driver approaching an intersecti on where another vehicle was arriving perpendicularly. The factors man ipulated were the presence or absence of a spatial reference point (ro ad sign near the intersection), environmental complexity (''road'' or ''spot'' scenes), and the degree of field dependence/independence. Nin e field-independent (FI) subjects and seven field-dependent (FD) subje cts were asked to predict whether the other vehicle would reach the in tersection before or after they would. Their responses were analyzed. Overall, subjects' judgements were more accurate with road environment s and with a road sign, suggesting that the relative motion of the oth er vehicle with respect to fixed elements in the environment provides additional useful information. FI subjects wire significantly more acc urate than FD subjects, suggesting that the former are better at picki ng up relevant dynamic information in a complex environment. (C) 1998 Elsevier Science B.V. All rights reserved.