The first, the least and the last: Spatial asymmetries in memory and their relation to script trajectory.

Serial positioning biases are well documented and generally take a U-shaped form, with better memory for first (primacy) and last items (recency). Here, we test the hypothesis that the relative strength of primacy and recency depends on script direction. When presented with large arrays of images, people are expected to first direct attention to the side where they usually start reading (in our case, left among Italian, and right among Arabic speakers) and to then scan the remaining images along the habitual text trajectory. Besides supporting the predicted scanning direction with an eye-tracker methodology, Study 1a (n = 56 Italians) provides evidence for a spatial memory advantage for images positioned to the left. Study 1b (n = 34 Italians) shows that people are aware of the asymmetric scanning and the memory advantage deriving from it. Study 3 (n = 67 Italian and n = 44 Arabic speakers) shows opposite memory biases in the two samples, with best performance for images on the left among Italian and for images on the right among Arabic speakers. Together these studies contribute to the growing literature showing that scanning habits due to script direction exert a subtle influence on basic cognitive processes.