by Aparna Nadig, Associate Professor, Communication Sciences and Disorders, McGill University
As a researcher of social cognition I am very aware of the research showing that more and varied language input enhances a child’s language development and confers long-term linguistic and academic advantages. It is wonderful to see that this research is being translated into public programs and campaigns in the US that encourage parents to read, talk, and sing to their kids with the goal of decreasing academic disparities experienced by underprivileged groups. I am also a new mother, and I make a point of adding lots of language to interactions with my daughter. There are moments in the day, however, when I’m just too tapped out to summon up any more talking, singing or reading to my very active toddler. Digital media screens and their varied content of TV, videos, apps and games are increasingly ubiquitous in our daily lives and those of our children. Does language input from these media have similar benefits to my direct interaction for those times that I need a break? Being a researcher I decided to look at the data.
Some research observes babies in their home environment and measures their language learning over time. This research highlights the fact that “the more language input the better” rule does not always hold; the nature and source of the input matters. Weisleder & Fernald (2013) measured the amount of speech that was directed towards 19-month-olds over the course of their day; they found that amount of speech directed at the toddlers predicted their vocabulary size and their efficiency at processing familiar words 6 months later. On the other hand, the amount of overhead speech did not have the same effect – overheard speech included conversations between other members of the family or on the telephone. Stretching the notion of language input to the extreme, background TV doesn’t cut it: for example, Barr et al. (2010) found that higher levels of exposure to adult-directed TV at age 4 was associated with lower rather than higher vocabulary, while exposure to child-directed TV had no effect.
Other research looks at the infant’s ability to learn new words in the laboratory. Krcmar, Grela & Lin (2007) and Krcmar (2010) directly compared infants’ ability to learn new words from live human teachers versus learning words from that same teacher presented on video. In the laboratory task the toddlers were asked to pick out one novel object from a group of five after they had been told the new object’s name five times. Generally, infants aged 13 through 20 months are more likely to learn the new word from a live human teacher. Toddlers aged 21 to 24 months of age were better equipped to learn from video demonstration as well as live teachers. Another comparison looked at whether infants and toddlers can learn from baby-targeted TV programming, specifically a Teletubbies clip using a voice-over from the same adult to teach the new word (Krcmar, Grela & Lin, 2007). Learning from the Teletubbies clip was the poorest of the three conditions, though older toddlers close to their second birthday and those who had larger vocabularies showed some indication of learning the word.
In future blogposts I will discuss why infants and young toddlers under the age of 20 months or so have difficulty learning language from video and explore characteristics of media that might be helpful for older toddler and child learning. For now however I conclude that it is best to continue to focus on live interactions with my own 13-month-old toddler. Luckily she’s got plenty of other people in her daily life to keep the language input coming when I need some down time!