The benefits of music for babies are well established, leading many parents to introduce their offspring to this form of entertainment from birth. A new US study, however, reports that infants are more exposed to spoken words than to melodies.

Researchers at the University of Washington came to this conclusion after analysing day-long audio recordings of sounds made by several infants aged six, 10, 14, 18 and 24 months.

“Quite a few studies have looked at how many words babies hear at home, and they’ve shown that the amount of infant-directed speech is important in language development. But we realised we don’t know anything about what type of music babies are hearing and how it compares to speech,” corresponding author Christina Zhao said.

The researchers found that babies are far more exposed to spoken words than to music in their daily lives. When they do listen to music, it’s often through electronic devices, rather than “live”. The adults they interact with rarely sing songs or lullabies to them.

“We’re shocked at how little music is in these recordings. The majority of music is not intended for babies; we can imagine these are songs streaming in the background or on the radio in the car. A lot of it is ambient,” Zhao said.

The findings of this research, published in the journal Developmental Science, also found that parents tend to overestimate the frequency of their musical and verbal interactions with their babies. And, as Zhao noted, “in our data, we see that speech and music input are not correlated – so it’s not like a family who tends to talk more will also have more music”.

And yet, they might do well to do so: studies have shown that music can be a powerful cognitive and cerebral stimulant. In 2019, Swiss researchers discovered that music promotes the development of sensory and cognitive functions in premature babies, as it modifies the brain’s biochemical processes, enhancing cerebral plasticity.

But the babies didn’t just listen to just any kind of song: for their research, the Swiss team specially commissioned composer Andreas Vollenweider to create three melodies to accompany the infants’ phases of waking, awakening and falling asleep.