Author accepted manuscript: A robust anchoring effect in linear ordering

The robustness of effects indicating a spatial component associated with abstract reasoning is tested. Judgements regarding hierarchical orderings tend to be faster and more accurate when the dominant element in any pair from the order (e.g., the older, richer) is presented on the left of the screen as compared with the right (left-anchoring effect). This signature effect is investigated in three conditions (Experiment 1), each implementing a different timing regime for the elements in each pair, during learning. Thereby, the construction of a mental representation of the ordering was exposed to a potentially competing spatial simulation, that is, the well-known "mental timeline" with orientation from left (present) to right (future). First, the left-anchoring effect for order representations remained significant when timeline information was congruent with the presumed left-anchoring process, that is, the dominant element in a pair was always presented first. Second, the same effect remained also significant when the timeline-related information was random, that is, the dominant element being presented either first or second. Third, the same effect was found to be still significant, when the timeline-related information was contrary to the left-anchoring process, that is, the dominant element being presented always second. Experiment 2 replicates the target effect under random timeline information, controlling for colour as a stimulus feature. The results are discussed in the context of a theoretical model that integrates basic assumptions about acquired reading/writing habits as a scaffold for spatial simulation and primacy/dominance representation within such spatial simulations.