Nursery rhymes have long taught us about life. For example, Old MacDonald offers lessons in agriculture, The Teddy Bears’ Picnic provides a terrifying warning about wildlife and The Wheels on the Bus teaches us about how annoying public transport can be.

But nursery rhymes have a lot more to offer, according to researchers from the University of Cambridge’s Centre for Neuroscience in Education, particularly in optimising the developing language system of children.

Indeed, Professor Usha Goswami, director of the centre, and her team have found that nursery rhymes are “the perfect rhythmic template for the developing brain”.

“If you look at rhythmic language, you find that it is typically used at nursery age in many languages,” she explains. “This suggests that rhythmic language is somehow helping the developing language system get itself up and running.”

Why might this be?

“It’s complicated, because speech is a very complicated percept,” she says. “But basically, when you speak, you’re making air molecules move. So you’re creating a wave of sound pressure that comes to someone else’s ear, and then gets converted into neural signals in the brain. So there’s an overall wave of pressure coming, which you can think of as the intensity envelope or the amplitude envelope of speech.

“And if you look at different types of speech, like nursery rhymes, you find that there’s more structure in that envelope. There are amplitude modulations, which are variations in intensity, at three different temporal rates.”

First up, she explains, there’s the amplitude modulation that occurs twice a second, which is roughly consistent with the stressed syllable rate across languages (most speakers of most languages produce a stressed syllable twice a second).

Then there’s a faster rate, at five times a second, which corresponds roughly to the syllable level (most people say about five syllables a second).

Finally, there’s an even faster rate, known as the onset rhyme level, where any syllable is divided at the amplitude peak when you speak the vowel (like “st-ar” in Twinkle, Twinkle, Little Star).

“The idea is that when the brain is encoding language, it’s encoding these amplitude modulation statistics, which are foregrounded both in infant-directed speech [also known as baby talk] and in English nursery rhyme,” Goswami says. “So, with this rhythmic template in a nursery rhyme, you get perfect temporal alignment of these three different rates of amplitude modulation, so there’s an optimal stimulus to the brain.”

This is because the brain cells in the auditory cortex also oscillate or respond at those three rates, she explains. There are networks of cells that are always alternating between excitation and inhibition at those rates and when speech starts, they all line themselves up so that they’re in time with the patterns of the speech signal.

“The idea is that the nursery rhyme actually optimises that process, especially if you’re singing it - so you’ve got this perfect temporal alignment,” she explains. “In a way, it makes it easier for the brain, which can have a perfect hierarchy of firing patterns that matches the amplitude modulation patterns in nursery rhymes.”

Essentially, the developing brain is working out how to predict what’s coming next in speech and it does this through predicting where stressed syllables are going to be. That system will eventually be able to deal with the natural way that people speak (which is not rhythmically regular), but researchers hypothesise that, at the beginning, the brain needs everything to be as exaggerated as possible. When you speak rhythmically, Goswami explains, you’re deliberately speaking to a rhythm, so everything is temporarily aligned in the speech signal as well. “That’s why we use infant-directed speech,” she says. “We’re really exaggerating - without knowing it - this two-hertz band of amplitude modulation.”

While this is exciting research in its own right, it is particularly important for children with dyslexia. Research suggests that such children find it more difficult to hear rhythm, says Goswami. This means that they can struggle to recognise whether patterns of beats are the same and they can similarly find it hard to identify the syllable “beats” in language.

“I’ve spent the past 20 years looking at the brain basis of dyslexia and finding problems in auditory processing,” she says. “The basic auditory processing of rhythm in any sound seems to be atypical in dyslexia.”

Researchers have found the link between dyslexia and an inability to hear certain rhythms in speech in several languages as well as English, including Chinese, French and Hungarian. Goswami currently has a study under way looking at infants who have a family risk of dyslexia (where one or both of their parents has dyslexia), and has already found that they’re worse at picking up on these acoustic parameters by the age of 10 months, which suggests that this atypical processing is present from birth.

And this has well-established knock-on effects on literacy, she explains, with “decades of research” showing that differences in being able to access the sound structure of words (known as phonology) links to differences in reading ability.

“Perceptually, it’s like being colourblind,” she continues. “If you’re colourblind, your brain doesn’t get the red-green distinction in the wavelengths of light. It doesn’t mean you can’t see, but you see everything a bit differently to everyone else.

“This is the same idea. It doesn’t mean you can’t learn language, but you’re using a slightly different perceptual representation to everybody else. And that doesn’t seem to matter for natural language production and comprehension, but it does matter when you come to learn to read.”

Fortunately, Goswami and her team have found that certain activities - such as tapping along to a song - can enhance children’s rhythmic timing abilities, while other methods, such as clapping out the syllables in words, can help them to hear the rhythm in language. And they have also found that nursery rhymes are effective, for the reasons stated above.

In fact, she says, anything that can improve awareness of the make-up of words - how they sound, the syllables, whether they rhyme with other words and so on - will improve understanding, and have an impact on reading. “Most of us learn to do this at school, to think about words not just in terms of what they mean, but how they sound,” Goswami says. “These things are implicitly there as you’re learning a language, but you need to reflect on them to become literate.”

Nursery rhymes are one effective - and enjoyable - way to engage in this reflection but, she explains, there are lots of others, too. You can practise repeating or singing a simple rhythmic phrase, but changing the syllable length of a key word while preserving the rhythm (“Happy Birthday, Dear Duck/Happy Birthday, Dear Giraffe/Happy Birthday, Dear Camel/Happy Birthday, Dear Dinosaur”, for example); or you could try playing the DeeDee game, in which a simple phrase is spoken in strong (DEE) versus weak (dee) “DeeDees” (“Jack and Jill went up the hill”, for example, has a strong-weak syllable structure, so the DeeDee version would be “DEE dee DEE dee DEE dee DEE”).

And in terms of future developments, Goswami says the research in this area could have far-reaching implications for how dyslexia is managed, with the possibility of creating a device to adjust sounds to mitigate for these processing differences.

“The idea would be that we could actually change the speech signal by clever filtering, so that those parameters are even more exaggerated,” she says. “That’s what our dyslexia research is trying at the moment, just taking somebody, say, saying a nursery rhyme, and then really amplifying the rise times, especially for the two-hertz modulation, which is where the dyslexic brain seems to be atypical.

“We’re trying to make it a sort of super-duper stimulus for the brain. And if it works, then in the future, if you have dyslexia, you would get one of these devices, so that you hear all speech with these portions amplified that your brain doesn’t get so well, and then you develop the same phonological system as everybody else.”

Zofia Niemtus is deputy commissioning editor at Tes

This article originally appeared in the 7 June 2019 issue under the headline “Tes focus on...Language development and dyslexia”