Ordinal knowledge and spatial coding of continuous and discrete quantities in infancy

An important issue in human cognition concerns the origins and nature of the capacity to represent number. A great deal of research has focused on infants’ comprehension of the cardinal properties of number but another essential component of the concept of number is ordinality, which refers to the inherent “greater than” or “less than” relationships between numbers. Until recently, the development of this aspect of human numerical cognition in infancy had received little attention. while little is know. The aim of the current series of studies was to investigate whether the ability to appreciate ordinal relationships between numerical magnitudes is present in preverbal infants at an earlier age than previously reported. The current investigation thus includes a series of 6 experiments conducted with infants of 4 and 7 months of age and provides evidence for the debate about functional affordances of infants’ numerical representation, demonstrating that, under certain conditions, the ability to detect and grasp ordinal information embedded in non-numerical and numerical sequences of visual stimuli could be present early in infancy, at respectively 4 months and 7 months of age. Importantly, this study provided also evidence that account for the existence of a basic mapping of number to space the presence, showing that 7-month-old infants are able to link oriented spatial codes to representations of numerical magnitude.