Is more always up? Evidence for a preference of hand-based associations over vertical number mappings

It has been argued that the cognitive mapping of vertical space and number plays a fundamental role for our understanding of numerical concepts and should therefore dominate over other numerical associations. However, convincing evidence for an association of numbers and vertical bimanual responses is still lacking. This study therefore examines the presence of the vertical SNARC effect in a number classification task by directly comparing anatomical hand-based (left/right) and vertical associations. Our mixed model of linear spatial-numerical associations revealed a preference of anatomical over vertical number associations since no evidence for a vertical but clear support for an anatomical SNARC effect was found. Only if the task requirements prevented participants from using a number- hand associations, because the hand-to-button assignment was alternated frequently, numbers were associated with the vertical dimension. Taken together, the present findings clearly question the importance of vertical associations for the conceptual understanding of numerical magnitude as hypothesized by some embodied approaches to number cognition and suggest a preference for ego- over geocentric reference frames for the mapping of numbers onto spac