1 . Phonetic (语音) information—the smallest sound elements of speech - is considered by researchers to be the basis of language. Babies are thought to learn these small sound elements and add them together to make words. But a new study suggests that phonetic information is learnt too late and slowly for this to be the case. Instead, rhythmic (有韵律的) speech helps babies learn language and is effective even in the first few months of life.

Researchers from the Trinity College Dublin investigated babies’ ability to process phonetic information during their first year. Their study, published in the journal Nature Communications. found that phonetic information wasn’t successfully encoded (编码) until seven months old, and did not occur very often at 11 months old when babies began to say their first words. From then individual speech sounds are still added in very slowly—too slowly to form the basis of language.

The researchers recorded patterns of brain activity in 50 babies at four, seven, and eleven months old as they watched a video of a primary school teacher singing 18 nursery rhymes (童谣) to a baby. They found that phonetic encoding in babies appeared inchmeal over the first year of life, beginning with labial sounds (e.g. “d” for “daddy”) and nasal sounds (e.g. “m” for “mummy”), with the “read out” progressively looking more like that of adults.

“The reason why we use nursery rhymes is because that is the best way for babies to discover and connect sounds with language, so we are teaching them how to speak,” said Giovanni Di Liberto, lead author of the study at Trinity College Dublin in Ireland. “Parents should talk and sing to their babies as much as possible or use baby-directed speech because it will make a difference to language outcome,” she added.

2 . It’s often said that we human beings can dream in a foreign language. Could dreaming in a foreign language improve our memory? Does dreaming in a foreign language mean we are making progress in learning that language?

Before we look at multilingual (多语言) dreams, first we need to look at sleep. The connection between sleep and language can be applied to how we learn any language, including our native language. Even adults still learn about one new word every two days in their first language. But, if we are going to remember that new word better, what matters is that we need to connect it with what we have learned. And in order to do that, we “need to have some sleep”, says Gareth Gaskell, a professor at the University of York.

It’s during sleep that the integration (整合) of old and new knowledge happens. At might, one part of our brain — the hippocampus — takes whatever new information it receives during the day and passes it on to other parts of the brain to be stored. The role that dreams play in this night-time learning process is still being studied, but “it’s entirely possible that during multilingual dreams, the brain is trying to connect the two languages”, says Marc, a researcher at a university in Bern, Switzerland.

So having multilingual dreams could mean that our brain is trying to remember a new word or phrase. However, it could also have an emotional (情感) significance. Danuta, a professor of psycholinguistics at the University of Silesia in Poland, suggests that multilingual dreams can express “fears or wishes” around learning a foreign language, including the wish to be a local speaker or to be accepted within a certain community.

We clearly still have a lot to learn about multilingual dreams, but one thing seems certain: if you’re trying to learn a new language, you can sleep on it.

4 . You may not know it, but your brain is already an amazing vocabulary learning machine. When you read or listen to something, your brain doesn’t take each word at face value: it’s continuously taking statistics about which words appear together regularly so that it can expect what’s coming next and process speech faster.

Our brains continuously release electrical signals, which change depending on what task your brain is dealing with. Scientists can use a technique to read some of these to study how your brain processes language.

One of these signals, called N400, changes depending on whether words make sense in context or not. The N400 is relatively small for expected word combinations, like coffee and cream, and increases in height for unexpected word combinations, like coffee and cap. This means that scientists can read the N400 height to analyze the kind of expectations you have about which words usually appear together.

In language learners, the N400 changes based on proficiency （熟练程度）. The better people get at a language, the closer their N400 pattern is to native speaker’s. This means that an important part of language proficiency is taking statistics and building expectations about what words usually appear together, just as native speakers do.

To get better at this, we need to flood our brains with loads of natural content, so we can build up a picture of which kinds of words usually appear together. Reading is a great way to do this and there’s lots of research that shows that reading works wonders for your vocabulary skills.

However, it is important to remember that if there are too many unknown words, it can be difficult to figure out what they mean from the context. And it is unpleasant having to stop every two miles to look up a word. Graded readers, which are books adapted to make them easier to understand at lower levels, are perfect for learners of foreign languages.