Interaction during reading is key to language development

Interaction, not just the sound of words being read from a page, is the key to language development during reading.

That's according to a new study from the University of Iowa that looked at how mothers responded to their 12-month-olds during book reading, puppet play, and toy play. What researchers found is the babies made more speech-like sounds during reading than when playing with puppets or toys. They also discovered mothers were more responsive to these types of sounds while reading to their child than during the other activities.

The findings might explain why book reading has been linked to language development in young children.

"A lot of research shows that book reading even to infants as young as six months of age is important to language outcomes, but I'm trying to explain why by looking at the specifics, which could be responding to speech-like sounds," says Julie Gros-Louis, assistant professor of psychology at the UI and corresponding author on the study, published in January in Language Learning and Development.

"If we know what specific interactions are occurring between caregiver and child and we can link that to language outcomes, then it wouldn't just be telling parents, 'Read a lot of books to your kids,'" Gros-Louis adds. "That would definitely be important to tell them, but you could also identify specific behaviors to do during book reading."

The study also found that no matter the context, mothers' responses to speech-like sounds were often imitations or an expansion of the sound. For example, if the baby said, "Ba," the mother would respond with "Ba-ba" or "Ball," even if it had nothing to do with the story being read. Mothers frequently provided labels during reading, too.

Gros-Louis says she used mothers and their babies for this study because their interactions have been studied more than those between fathers and their children. Thus, she could more readily compare her findings to past studies.

In this case, researchers observed the interactions of 34 mothers and their 12-month-olds during three 10-minute periods of different activities: puppet play, toy play, and book reading. The hand puppet was a cloth monkey; the toy was a Fisher-Price barn with manipulative parts, such as buttons to push and knobs to turn; and the books had bright pictures and simple sentences rather than single words or labels. The babies were seated in a high chair to control proximity to their mothers and to prevent them from getting up and moving around the play room.

Researchers then coded each child's vocalizations and his or her mother's responses. Vocalizations included any sound the baby made except distress cries and fusses, hiccups, coughs, and grunts. Mothers' responses were coded for verbal content in the following categories: acknowledgments ("mmm-hmm," "uh-huh"); attributions ("it's pretty"); directives ("push that"); naming ("it's a ball"); play vocalizations ("getcha!"); questions; and imitations/expansions.

"The current findings can contribute to understanding how reading to preverbal infants is associated with language outcomes, which is not well understood in contrast to reading interactions with older toddlers," according to the study.

This isn't the first time Gros-Louis has studied how mothers respond to the babbling of their infants. In a study published in 2014, she and researchers from Indiana University found mothers who consciously engaged with their babbling 8-month-olds could accelerate their children's vocalizing and language learning.