Polarity correspondence does not explain the SNARC effect

Polarity correspondence does not explain the SNARC effect Julio Santiago (santiago@ugr.es) Department of Experimental Psychology, University of Granada Campus de Cartuja, 18071 Granada, Spain Daniel Lakens (D.Lakens@tue.nl) School of Innovation Sciences, Eindhoven University of Technology Postbus 513, 5600 MB Eindhoven, The Netherlands Abstract Conceptual metaphor congruency effects have been interpreted as evidence for the notion that the representation of abstract conceptual dimensions (e.g., power, evaluation) rests on more concrete dimensions (e.g., space, brightness). However, an alternative account based on the notion of polarity correspondence has recently received empirical support from studies about the mapping between affective evaluation and morality on vertical space. We tested the polarity correspondence account in the domain of number, which shows well-known congruency effects with lateral left-right space (the SNARC effect). Response polarity was manipulated by varying keyboard eccentricity in both parity (odd-even) and quantity (larger-smaller than 5) tasks. Response eccentricity did not modulate the SNARC effect. In a final experiment, the orthogonal Simon effect was modulated by the manipulation of response eccentricity. We conclude that polarity correspondence does not provide an adequate explanation of conceptual congruency effects in the domain of number. Keywords: conceptual metaphor; polarity correspondence; SNARC; number; space; response eccentricity; orthogonal Simon. Introduction Recent years have witnessed a strong interest in the possibility that the mental representation of abstract concepts relies in a deep sense on more concrete concepts (see Landau, Meier, & Keefer, 2010, and Santiago, Roman, & Ouellet, 2011, for reviews). Under this view, an abstract concept or conceptual domain imports structure and content from a better understood, more clearly delineated, more concrete conceptual domain. For example, time is understood as physical motion from one location to another (Clark, 1973), and power is linked to physical size (Sorokowski, 2010). Such a view suggests that the mental representation of concepts is hierarchically structured, such that more concrete concepts are more directly linked to perceptual-motor experiences, and these in turn are used to support the understanding of more abstract levels. Therefore, the whole human conceptual structure is anchored to, or founded upon our embodied interaction with the external world, which is why Santiago, Roman, and Ouellet (2011) called it the Solid Foundations view. An important source of evidence for such a view comes from conceptual congruency tasks. In these tasks, a concrete and an abstract dimension are factorially crossed. Participants' main task requires the processing of the abstract dimension, and the effects of the concrete, task-irrelevant dimension are measured. Typically, both dimensions interact, such that a particular combination of concrete and abstract conditions shows better performance. This metaphorical congruency effect is often interpreted as revealing the use of underlying concrete representations to support the abstract judgment. A well-known example is the Spatial-Numerical Association of Response Codes (SNARC) effect (Dehaene et al., 1993). In a typical SNARC task, the participant has to make a numerical discrimination, such as deciding whether a number is odd or even, by means of key presses. The responding hand (left or right) is the task-irrelevant concrete dimension: in some blocks the “odd” response is given by a left-hand key press and the “even” response by a right-hand key press. In other blocks, the mapping is reversed. The standard result, now widely replicated, consists in better performance when responding to a small number with the left hand and to a large number with the right hand versus using the reverse mapping (see Wood, Willmes, Nuerk, & Fischer, 2008, for a review). The SNARC effect has most often been interpreted as evidence for the use of a spatial left-right line to mentally represent number magnitude. However, Lakens and coworkers (Lakens, Semin, & Foroni, 2012; Lakens, 2012) have proposed that it may not be necessary to resort to concrete representations of any kind in order to account for many of the published metaphorical congruency effects. Their view rests on purely structural features of dimensional concepts based on the concept of markedness and on the principle of polarity correspondence proposed by Proctor and Cho (2006), which applies when two or more dimensions are simultaneously manipulated in a task. The concept of markedness has a long standing tradition in linguistics (Greenberg, 1963) and psycholinguistics (Clark, 1969). The two poles of most conceptual dimensions (e.g., happiness or tallness) do not seem to enjoy the same representational status. One of them, which we will refer to as the +pole, is used to refer to the whole dimension, whereas the other, the -pole, is used to refer only to itself (e.g., compare “how tall is John? ” versus “how short is John? ”: the former does not presuppose that John's height is in any specific range, whereas the second question suggests that John is short). The +pole is more frequent in language and enjoys a processing advantage compared to the -pole (Clark, 1969). Proctor and Cho