Updated: Feb 25
#FreshFromTheLab: We recently attended a fantastic talk by Dr Danielle Matthews of the University of Sheffield. She studies the way babies interact with their mums – something we all care a lot about!
We all know what it looks like when baby is ready to communicate with us. There’s a lot of ‘nonsense’ babbling, pointing, laughing, and maybe some yelling. What do all these behaviours have in common? They’re called ‘pre-linguistic behaviours,’ and they mean that baby is ready to communicate! How exciting! Dr Matthews studies these behaviours and how they relate to baby’s later language development, as well as how caregivers can facilitate baby’s development through interaction.
Interestingly, while we always think of mum/dad shaping baby’s behaviour, baby can also shapes their interactions too! This is important to Dr Matthew’s research – babies ‘pull’ interactions out of mum/dad, thereby learning more about bits of the world they’re interested in. Imagine a situation where baby drops an orange block in your lap. How might you respond? Probably by saying something like, “Thank you for giving me the block! What colour is the block? Is it an orange block?” parents often respond to baby this way without thinking, but actually this kind of response gives baby loads of information about the world exactly at the moment they’re ready for it. Baby now knows this thing is called ‘a block’ that has a ‘colour’ that’s called ‘orange.’ Cool!
Dr Matthew’s first study examined how both mum’s and baby’s behaviours help to pave the way for early language development. In order to address this question, they took many hours of videos of mum and 11-month-old baby playing in a natural environment – at home, with their typical toys, on a typical day. Research assistants then poured over the content for years to follow, coding each moment to label different behaviours of all 58 mum-and-baby pairs. Some examples of behaviours they labelled were vocalisations (e.g., mum talking, baby babbling), gestures (e.g., pointing), and gaze location (e.g., direct eye-contact). The researchers then followed-up on the same baby’s language development when they were 15, 18, and 24 months old. Mums filled out extensive questionnaires about how many words baby has, the complexity of their sentences, use of tense/plurals, and other important language development milestones. Dr Matthews and her team then conducted correlations between behaviours at 11 months in natural play and language development at 15, 18, and 24 months.
So, what did they find?? Amazingly, they found that the best predictor of language development at each timepoint was the number of infant vocalisations that occurred during windows of coordinated gaze with mum, who then responds in a timely and sensible manner. To make this more concrete, let’s go back to the example of the orange block. Baby gives mum the block and says, “Ba!” (a vocalisation) while looking at mum, waiting for a response. The kind of reaction that helps baby grow, according to Dr Matthews’ research, would be for mum to look to baby whilst responding as she does – “Thank you for giving me this block! What colour is the block? Is it an orange block?” Mum may hold up the block, point to it, or otherwise indicate to baby that she is responding specifically to baby’s interest in the block. Put simply, Dr Matthews finds that mums who engage in this kind of communication tend to have babies with better language outcomes at 15, 18, and 24 months.
Dr Matthews’ second study looked at the same mum and baby behaviours and language outcomes as the first study, this time among infants with severe to profound hearing loss. This is an important question because patterns of communication between a hearing mum and hearing baby will be completely different to those of a hearing mum and deaf baby. While hearing babies may be able to look at the orange block while mum labels it, a deaf baby cannot rely exclusively on verbal input whilst simultaneously exploring the visual world. Instead, a deaf baby is more likely to look at the block intently, look back to mum for some information, then return to the block. While this pattern isn’t “worse” than a hearing baby’s pattern, the mismatch between hearing mum and deaf baby has implications for baby’s language development.
Dr Matthews’ study second study found that deaf babies produce fewer vocalisations than hearing babies. They also engage in fewer gestures, “show” and “give” behaviours with mum than hearing babies. Dr Matthews thinks this may be the case because early communication patterns between mum and baby are breaking down. If baby do not think their attempts at communication will be successful, they may make fewer attempts. Future research is needed to understand these patterns.
In her last study, Dr Matthews and her team created an informational video for parents of deaf infants about early social communication patterns. In this phase of research, her team showed the videos to mums and got their opinions about whether they found them clear, effective, and relevant to their needs. The videos suggested that mums of deaf babies pay extra attention to getting baby’s visual attention before explaining something about an object or the world. It also encouraged learning some sign language to help bridge the gap between baby and mum’s communication styles. Overall, mums found the videos to be really helpful!
What does this research tell us overall? Just that you should hang out with your baby! When you do, put your phone aside and follow baby’s lead. Ask them questions, teach them about the toys they like, and let THEM guide YOU!