TY - JOUR AU - Uller, Claudia AU - Urquhart, Callum AU - Lewis, Jennifer AU - Berntsen, Monica PY - 2013 M3 - Original Research TI - Ten-Month-Old Infants’ Reaching Choices for “more”: The Relationship between Inter-Stimulus Distance and Number JO - Frontiers in Psychology UR - https://www.frontiersin.org/articles/10.3389/fpsyg.2013.00084 VL - 4 SN - 1664-1078 N2 - Animals and human infants discriminate numerosities in visual sets. Experiments on visual numerical judgments generally contrast sets in which number varies (e.g., the discrimination between 2 and 3). What is less investigated, however, is set density, or rather, the inter-stimulus distance between the entities being enumerated in a set. In this study, we investigated the role of set density in visual sets by 10-month-old infants. In Experiment 1, infants were offered a choice between two sets each containing four items of the exact same size varying in the distance in between the items (ratio 1:4). Infants selected the set in which the items are close together (higher density). Experiment 2 addressed the possibility that this choice was driven by a strategy to “select all in one go” by reducing the size and distance of items. Ten-month-olds selected the sets with higher density (less inter-stimulus distance) in both experiments. These results, although bearing replication because of their originality, seem consistent with principles in Optimal Foraging in animals. They provide evidence that a comparable rudimentary capacity for density assessment (of food items) exists in infants, and may work in concert with their numerical representations. ER -