Discrimination and ordinal judgments of temporal durations at 3 months.

This study presents the first evidence that 3-month-old infants success in a timing matching task and in an ordinal timing task, when numerical information is controlled. Three-month-old infants discriminated brief temporal durations that differed by a 1:3 ratio, relying solely on temporal information. Moreover, at 3 months of age infants were able to discriminate between monotonic and non-monotonic time-based series, when numerical and temporal information were inconsistent. These findings strengthen the hypothesis that a magnitude representational system for temporal quantities is operating very early in the ontogenetic development.