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New research from The ManyBabies Consortium led by Michael Frank of Stanford University reports that babies from different cultures around the globe prefer infant-directed speech (IDS) over adult-directed speech (ADS), regardless of the language being spoken.
IDS is synonymous with baby talk, which is also referred to as motherese, fatherese, or parentese.
The latest international, multi-lab study (Frank et al., 2020) of baby talk tested 2,329 babies in 16 countries on their degree of preference for infant-directed speech. The findings were published on March 16 in the journal Advances in Methods and Practices in Psychological Science.
The ManyBabies Consortium's mission is the replication of influential experiments in developmental psychology using multiple laboratories. As their homepage explains, "Our goal is to bring labs together to address difficult outstanding theoretical and methodological questions about the nature of early development and how it is studied."
According to the consortium, their recent study of infant-directed speech preference is the most extensive multi-site study to examine how infants around the globe respond to baby talk.
Michael Frank is a developmental psychologist and director or the Stanford Language and Cognition Lab. In a Stanford news release, he said, "Often parents are discouraged from using baby talk by well-meaning friends or even health professionals. But the evidence suggests that it's actually a great way to engage with your baby because babies just like it—it tells them, 'This speech is meant for you!'"
For this study on infants' relative preference for IDS over ADS, Michael Frank and other members of the ManyBabies Consortium used three methods (e.g., head-turn preference, eye tracking, and central fixation) to assess babies' speech preference.
The average age of the babies who participated in this research was around nine months (with a range of 3-15 months old). This research was conducted in 67 different laboratories across Australia, Asia, Europe, and North America. Infancy research on IDS vs. ADS speech preference is underway by members of the ManyBabies Consortium in Africa and South America.
"We wanted to get labs together from around the world to test how similar or different babies' preferences are across different environments," Frank said. Overall, babies from every international site that has submitted results thus far have shown a preference for infant-directed speech over adult-directed speech.
The latest research by Frank et al. on the universal preference for IDS among infants dovetails with previous research (Piazza et al., 2017), which found that mothers around the globe intuitively shift their vocal timbre from ADS to IDS when speaking to infants. This study, "Mothers Consistently Alter Their Unique Vocal Fingerprints When Communicating with Infants," was published in Current Biology.
Elise Piazza and colleagues at Princeton University found that most mothers systematically shifted to infant-directed speech when communicating with babies. This is a multicultural phenomenon that occurs across a wide variety of languages. "Importantly, this shift [to motherese] was similar across languages, suggesting that such alterations of timbre may be universal," the authors conclude.
Why Is Baby Talk During Adult-to-Adult Communication So Prevalent?
It's not surprising that babies around the globe prefer infant-directed speech. What is surprising (to me) is how many "grown-up" couples also seem to enjoy baby talk. Why is this?
A post from 2019 by fellow Psychology Today blogger Karen Wu, "4 Reasons Why Baby Talk Is Good for Couples," offers four evidence-based reasons that help to explain why romantic partners often communicate with each other using IDS-like speech.
Wu cites a landmark study (Bombar & Littig, 1996), which found that couples who use baby talk tend to be more securely attached and happier. As Meredith Bombar and Lawrence Littig explain, "Communication intentions accompanying baby talk paralleled the hallmarks of attachment, especially affection and play. These and other results suggest that baby talk functions in the process of intimate personal connection."
Among the other potential reasons for adult baby talk that Wu discusses are the possibility that the pet names interwoven into baby talk (e.g., "mon bébé, "snugglepuffs," "my little schnookums") may fortify bonds between intimate couples and that the speech register of baby talk conveys affection. According to Wu: "Adults cite the motivations to be playful, affectionate, and vulnerable as the reasons for their baby talk."
In closing, the makers of this lighthearted YouTube video asked 100 people to talk like a baby.
References
The ManyBabies Consortium authors: Michael Frank, Christina Bergmann, Elika Bergelson, Krista Byers-Heinlein, Alejandrina Cristia, Rhodri Cusack, Kelsey Dyck, Caroline floccia, Judit Gervain, Nayeli Gonzalez, Kiley Hamlin, Erin Hannon, Danielle Kellier, Melissa Kline, Casey Lew-Williams, Thierry Nazzi, Robin Panneton, Hugh Rabagliati, Jennifer Rennels, Amanda Seidl, Daniel Yurovsky, Melanie Soderstrom. "Quantifying Sources of Variability in Infancy Research Using the Infant-Directed-Speech Preference." Advances in Methods and Practices in Psychological Science (First published: March 16, 2020) DOI: 10.1177/2515245919900809
