Volume 2 – From Birth to 29 Months

Number 8 – Cognitive Development in Children Aged 17 to 29 Months

From infancy to preschool age, young children develop numerous cognitive and language skills. Around the age of 18 months, they become capable of processing several items of information at the same time, which leads them to solving increasingly complex problems. The question is how this capacity to understand and interact with their environment develops in the first few years of life. The Québec Longitudinal Study of Child Development (QLSCD 1998-2002) provides a unique opportunity to study this question by assessing the development of mental-attentional capacity in a large representative sample of children born in Québec at the end of the 1990s. This paper paints a general portrait of the development of mental-attentional capacity in young children between 17 and 29 months. It also addresses the question of whether pronounced individual differences exist among children, and whether girls and boys differ in terms of the development of their mental capacity.