Time estimation deficits in childhood mathematics difficulties

Time perception has not been comprehensively examined in mathematics difficulties (MD). Therefore, verbal time estimation, production, and reproduction were tested in 13 individuals with MD and 16 healthy controls, matched for age, sex, and intellectual skills. Individuals with MD performed comparably to controls in time reproduction, but showed a tendency to be less accurate on tasks of verbal time estimation and time production. More specifically, these individuals overestimated the duration of a time interval in the verbal time estimation task and showed underproduction when required to produce a time sample. All previous significant comparisons remained significant after controlling for the effects of interval duration, working memory, attention allocation, and quantity estimation. These findings lead us to suggest that time estimation, and more specifically the "internal clock," is abnormally fast in individuals with MD. Results are discussed in terms of Meck and Church's model of temporal processing and Dehaene's triple code model for number processing.