Time processing impairments in preschoolers at risk of developing difficulties in mathematics

Purpose: Time processing problems in individuals with Development Dyscalculia has been studied to test the existence of a general magnitude system serving both modalities, as theorized by Walsh (2003). Time processing impairments were found in some cases, but they could be attributed to poor chronometric counting or poor calculations abilities, which can support reasoning on time in school-age children and adults. A way to disentangle this debate, is to explore the performance of young children, before they receive formal instructions for mathematics and develop these mathematical abilities.Method: For the present study, 30 5-years old children at risk for developing difficulties in mathematics (MD) and 30 typical developing peers (TD), matched for vocabulary, were selected from a larger group of preschoolers (N = 196) involved in a screening project assessing early numeracy. MD and TD children were administered with tasks investigating time reproduction and time discrimination skills; furthermore, their parents and teachers assessed participants’ “sense of time”, in terms of knowledge about the passage of time and use or comprehension of temporal words.Results and Conclusion: The MD group showed a poorer performance in time reproduction of 5-seconds intervals and in time discrimination; then, both parents and teachers reported a weaker “sense of time” for these children. By assessing time processing before children receive formal instruction for mathematics, we could rule out any possible confound played by explicit chronometric counting. These results are in favor of a common magnitude system that would be responsible for deficits in both numerical and temporal domains, already at early stages of life.