Reading/writing direction as a source of directional bias in spatial cognition: Possible mechanisms and scope

Becoming literate has been argued to have a range of social, economic and psychological effects. Less examined is the extent to which repercussions of becoming literate may vary as a function of writing system variation. A salient way in which writing systems differ is in their directionality. Recent studies have claimed that directional biases in a variety of spatial domains are attributable to reading and writing direction. This claim is the focus of the present paper, which considers the scope and possible mechanisms underlying script directionality effects in spatial cognition, with particular attention to domains with real-world relevance. Three questions are addressed: (1) What are possible mediating and moderator variables relevant to script directionality effects in spatial cognition? (2) Does script directionality exert a fixed or a malleable effect? and (3) How can script directionality effects be appropriately tested? After discussing these questions in the context of specific studies, we highlight general methodological issues in this literature and provide recommendations for the design of future research.