A PERCEPTUAL-COGNITIVE DIVIDING MODEL FOR THE INTEGRATION OF VELOCITY AND TRAVELED DISTANCE OF A MOVING TARGET BY LOCALIZATION RESPONSES Nuno de Sá Teixeira* 1 & Armando M. Oliveira* 2 *Center of Psychonomy and Human Factor, Institute of Cognitive Psychology, University of Coimbra 1 nuno_desateixeira@fpce.uc.pt 2 l.dinis@fpce.uc.pt Abstract Differently from phenomenological responses, Representational Momentum (RM) offers a continuous response measure in the field of dynamic representations and naïve physics. This property is taken here as a basis for the use of Information Integration Theory in a field where one-dimensional approaches are the rule and integration results lack entirely. The present work establishes a psychological multiplying/dividing model in a data pool obtained from a full factorial design Velocity (4) × Traveled Distance (3) with forward displacement error of the last seen position of the target as the measured response. Besides compliance with standard criteria (Anderson, 1982; Weiss, 2006), the model was tested for additional algebraically derived predictions concerning the relations of the intercept c 0 to interval and ratio-scale functional measures of the stimuli (Anderson, 1982; Masin, 2004). Implications of the findings are discussed, with an emphasis on estimation of c 0, which opens way to the functional measurement of both stimuli dimensions on a common ratio-scale. When a moving target that suddenly disappears is presented to subjects who are required to locate its vanishing point, an error in the direction of motion is typically found. Originally reported by Freyd & Finke (1984), this error was coined Representational Momentum, calling upon a “mental analogue” of physical momentum. Partly in agreement with the proposed analogy, RM was shown to increase with target’s velocity for both implied (Freyd & Finke, 1985) and smooth motion presentations (Hubbard et al, 2001; Hubbard & Ruppel, 2002), although no effect upon RM was apparent for target’s mass (Hubbard, 2005). In an attempt to merge existing evidence, Hubbard surmised that RM expresses a second order-isomorphism between mental representations and environmental invariants applying to the dynamics and kinematics of physical objects. Support for this view was provided under the form of several displacement effects consistent, for instance, with the internalization of principles of friction, centripetal force, or gravity (Hubbard, 2005). One important feature of RM is that, by being a continuous variable, it makes possible to address the issue of the integration of its contributing factors. Although many such determinants have been studied in isolation, they have seldom been considered in their joint action. Anderson’s Information Integration Theory (IIT: Anderson, 1981; 1982; 1996) is taken here as an appropriate framework for the study of RM multidetermination. Specifically, the present work focuses on the integration of target’s velocity and travelled distance by RM magnitude. In line with IIT methodology, all variables were fully crossed in factorial integration tasks, requiring a localisation response. As a supplementary between-subjects factor, two kinds of localisation response, either indirectly through a mouse cursor, or directly through a pointer, were used.