Spatial biases in infants’ learning of serial order: cross-cultural evidence for the role of experience

Recent evidence shows that preverbal infants raised in Western cultures represent increasing numerical order and extract rule-like patterns from visual sequences when items are presented from left to right, but not right to left. These findings match earlier demonstrations that adults and preliterate children represent numerical and/or non-numerical order along a spatial continuum whose directional attributes are shaped by reading-writing direction. Here we explored the developmental origins of the directional properties of order-space mapping by testing whether/how visual rule learning (RL) abilities are affected by the spatial orientation of the sequences in 115 Italian and 120 Japanese 7-month-old infants, whose cultures differ for the unidimensional vs multidimensional structure of their reading-writing systems. Infants were familiarized with rule-based sequences of visual shapes presented in a left-to-right, right-to-left, top-to-bottom or bottom-to-top orientation. They were then tested with six sequences of novel shapes depicting the familiar or a novel rule presented with the familiar orientation. Results showed that Italian infants succeeded at RL only when sequences were left-to-right and top-to-bottom oriented (Novelty x Direction, p=.019), while Japanese infants succeeded in all conditions, irrespective of the spatial direction of the sequences (ps<.040). We interpreted these results as evidence of early preferential directional encoding strategies of serial order and its internal representation that are modulated by culture through infants’ passive exposure and/or active imitation of directionally relevant culturally-driven routines. To further explore this argument, we will present data on caregivers’ directional behaviors during sessions of joint reading and toy construction.