When I was a young mother, I sang to my babies constantly. Singing comes pretty naturally to me, but I’ve noticed that most parents—even those who don’t normally carry a tune—seem to sing to their babies, even if just at bedtime..
Why? That’s the question tackled in recent studies by Sandra Trehub and colleagues. Trehub, a researcher at the University of Toronto, Mississauga, has studied the impacts of singing on babies and found that singing—more than talking—keeps babies calm and can lead to stronger social bonds with parents, improved health, and even greater language fluency.
“Babies recognize the voice much, much earlier than they recognize a mother’s face,” says Trehub. “Voice is a very powerful stimulus for an infant.”
Her work adds to a growing body of science that seeks to explain why music, and singing in particular, is ubiquitous in cultures around the world. It may be that music serves an important developmental function and that, even from birth, we are wired to pay attention to singing.
Singing calms babies more than talk
While it’s easy enough to observe parents singing to their babies and to see the positive emotional impacts of that singing, it’s harder to tease out whether singing itself is responsible for those effects—or some other factor, like a parent’s attention or soothing touch.
But in a study recently published in Infancy, Trehub, along with researchers Isabelle Peretz and Mariève Corbeil of the International Laboratory for Brain, Music, and Sound in Montreal, were able to do just that.
Trehub and colleagues put 7- to 10-month-old babies in a mildly stressful situation, a room with no other person in sight and no other stimulation. They then had the babies listen to audiotapes of either someone singing a song or speaking the lyrics to that song in an infant-directed manner—meaning, in an engaging, rhythmic, sing-song way. Interestingly, the babies were from French-speaking families, while the voices they listened to either spoke or sang in Turkish.
Observers who didn’t know which audio was playing monitored the babies’ faces, measuring how long it took for them to show visible signs of distress. Results showed that the babies listening to music remained calm twice as long as babies listening to speech—a finding that amazed Trehub.
“The babies listened to that Turkish music for nine minutes, which is pretty remarkable,” she says. “They were in a very boring environment—with no toys, no people—and that singing in the background was somehow keeping them engaged, even though it was an unfamiliar voice, an unfamiliar language, and an unfamiliar tune.”
In the second part of her experiment, Trehub and colleagues exposed another group of babies in a distraction-free room to speaking or singing, but this time the voices in the recording spoke or sang in their native language of French (though by an unfamiliar mother). By comparing how long the babies remained calm under the two conditions, the researchers again found that singing beat out speech, keeping babies calm about twice as long.
So apparently it’s not just the presence of a parent that makes babies pay attention to singing. Instead, something in singing itself engages and calms them.
“Even in this extreme case, where we’ve removed all of the aspects of the familiar context and the familiar materials, singing was still pretty powerful for the infants,” says Trehub.
Born to sing
What exactly fascinates babies about unfamiliar singing is unclear; but past studies on adults have shown that we humans appear to be wired to listen for musical patterns—melodies, rhythms, and lyrics—and that anticipating these patterns activates reward centers in the brain.
In a 2015 review of the science on music and emotion, researcher E. Glen Schellenberg writes that children as young as five years of age are able to express emotions in their singing by using pitch, intensity, and tempo, and that even younger children can pick out emotional cues in music. And a recent study found that unborn babies at 16 weeks appear to respond to music that is played to them inter-vaginally in the womb.
This implies that babies may have an inherent interest in musical patterns, which is similar to that of adults and would explain why they are particularly attracted to songs full of repetitious melodies and lyrics.
“Music has a lot of regularity in it,” says Trehub. “You have notes and musical phrases that repeat, so that you can become captivated, almost hypnotized by it. It happens to us as adults, and it certainly could happen to infants.”
But could the mesmerizing effects of singing be due to something else—perhaps positive associations from past experiences rather than the music itself? Trehub thinks not. She points to a study conducted in Japan with babies of deaf parents in which their newborns, who were not hearing-impaired, showed measurable responsiveness to infant-directed singing, even though they’d had no prior exposure to speech or singing. This suggests that the attention to singing is inborn and not dependent on parental training.
“Even in the newborn period, infants show responsiveness to singing,” says Trehub.
Singing also appears to produce positive physiological effects in babies. One recent randomized clinical trial showed that premature infants in an ICU unit exposed to parental singing demonstrated improved heart and respiratory rates, better sleep and feeding patterns, and better weight gain. A recent meta-analysis of research looking at the outcomes of using music therapy—and particularly singing—in neonatal units has shown similar benefits.
In an earlier study of Trehub’s, she found that babies with elevated levels of cortisol (a hormone affiliated with stress and arousal) had those levels reduce when they listened to singing, while babies with lower cortisol levels had their levels increase with singing. Because the babies in the study all appeared content during the experiment, Trehub concluded that singing has a modulating effect on cortisol, keeping it in just the right range for positive attention.
Singing helps babies connect
In a 2009 study conducted by Trehub and colleagues, she found that babies as young as 6-8 months of age could listen to recordings of people singing and match those recordings to videos of people singing with the sound turned off. This suggests that babies are naturally attuned to singing and auditory stimuli, in general, and that the skill may help them to identify important adult figures in their lives.
In fact, some children actually start singing before they speak, and some can sing extended portions of a song even though they may only be capable of producing a word or two via speech. Singing fosters fluency in sound production, says Trehub, which may help children learn language. However, she is quick to point out that there are no definitive studies that show singing improves a baby’s cognitive development.
“Do I think any of these things are a way to get an infant headed towards Harvard or Stanford? No, I don’t think so,” she says.
Instead, the evidence suggests that singing is most useful for helping babies to regulate emotion and focus attention, she says—both skills that could be linked to learning, perhaps, but that haven’t been tested in babies. But emotional regulation is pretty critical in its own right, because it can help make a baby more manageable. A happy, engaged baby can make a parent’s life a lot easier, which will encourage parents to think more favorably of their infant and form closer bonds.
“I wouldn’t ever tell anyone they have to sing; but people should do what gives them pleasure and share that with their baby,” says Trehub. “It’s not always what you do; it’s more the spirit in which you do it.”