Joint attention and vocabulary development in toddlers with Down syndrome and their peers with typical development: The role of maternal interactive style

J Commun Disord. 2020 Feb 12:84:105975. doi: 10.1016/j.jcomdis.2020.105975. Online ahead of print.

Abstract

Purpose: Joint attention is considered a prerequisite for language development. Although language is one of the most impaired domains in Down syndrome (DS), few studies have examined the relationship between caregiver behavior during episodes of joint attention and vocabulary development in these children. Consequently, our primary aim was to analyze the behaviors of caregivers of children with DS and of children with typical development (TD) in the early stages of vocabulary development. A second objective was to examine the kind of words that caregivers use to refer to the object that is the focus of attention. We also consider the concurrent relationship between joint attention and vocabulary development in both groups of children.

Method: We studied 28 children with DS and 28 children with TD, individually matched on mental age and gender, and their respective caregivers. The mean mental age for children with DS and children with TD was around 12 months. The mean chronological age of caregivers of children with DS and children with TD was around 35 years. Each child and his or her caregiver were video-recorded during a free-play session involving different objects.

Results: Although the total time engaged in joint attention was greater among caregivers of children with DS, caregivers of both groups of children were more likely to direct than follow their child's attentional focus. The caregivers of children with DS used a greater number of appropriate terms to refer to the object of attention. We found no significant correlation in either group of children between vocabulary development and joint attention behaviors.

Conclusions: The results may be due to the fact that the children studied are still very young in developmental terms and have yet to develop all the skills required for joint attention. At this early stage, directing the child's attention would promote the development of joint attention. A possible explanation for the lack of a correlation between vocabulary development and joint attention is that children may use an associative mechanism in the early stages of lexical learning, and hence the learning of new words is a slow process.

Keywords: Down syndrome; Joint attention; Language development; Maternal interactive style.