Early English Education: When Is the Right Time to Start? — Where the Critical Period Hypothesis Stands Today
Why this topic is on parents’ minds
“English is pointless unless you start by age 3,” “once the critical period has passed, you can’t become native-like”—I think anyone of child-rearing age has heard this at least once. It is also an expression often seen in ads for English conversation schools.
On the other hand, there are also voices saying, “Japanese people who start English in junior high school still become able to speak it,” and “children who started early aren’t necessarily good at English.” What does research actually say?
The idea of a “critical period”
In English learning, the “critical period” refers to a period after which acquiring a language becomes markedly difficult. Since the brain scientist Lenneberg proposed in the 1960s that “there is a critical period around ages 3-7,” it has long been supported.
However, as we read through recent research, it has become clear that the “critical period” is not a single period, but that each learning ability has its own, different sensitive period. Here we introduce two representative studies side by side.
The results of two major studies
Study A: Differences in telling sounds apart arise very early
research that has observed infants’ language processing for many years using brain imaging technology
has shown repeatedly that babies who at 6 months of age could tell apart the sounds of any language in the world rapidly lose, by 12 months of age, the ability to distinguish “sounds not in their native language”.
For example, multiple studies have confirmed that in babies raised hearing Japanese, the ability to tell English “L” and “R” apart declines sharply between 8 and 10 months of age. During the same period, American babies raised in an English environment, conversely, improve in this ability to tell them apart.
In other words, what this body of research shows is that for telling sounds apart (phoneme discrimination), decisive differences arise very early (within the first year of life).
Study B: Grammar can be acquired until past adolescence
research analyzing the relationship between the ability to acquire a second language and the age of starting, through a large online survey of about 670,000 people
showed that for complete mastery of grammar, high flexibility is maintained until around ages 17 to 18. This is a conclusion quite different from the earlier common belief of “a critical period at ages 3-7.”
In other words, what this large-scale study shows is that aspects such as grammar and vocabulary can be acquired well enough even after adolescence.
How to read the two studies
A and B look contradictory at first glance, but looking closely, you notice they speak about different abilities. A is about telling sounds apart, B is about grammar. Each ability has its own “sensitive period.”
Current research holds not that every ability has a uniform 'critical period,' but that sensitive periods differ greatly from ability to ability.
Source: Illustrated by the editorial team from Kuhl (2010), Hartshorne et al. (2018), and Birdsong (2018)
So my child is already 3—does that mean it’s already too late for pronunciation?
For telling sounds apart, it’s true that up to about the first year of life is an especially important period. From age 3 now, acquiring exactly the same ability to tell sounds apart as a newborn baby in an English-speaking country may be difficult. But that and “it’s too late for English” are separate matters.
Separate matters, meaning?
The vocabulary, grammar, and expressiveness your child will develop over many years from now—these make up a much larger share of English ability as a whole. As we discussed with Study B, grammar can be acquired until past adolescence, and vocabulary can even be increased throughout life. Pronunciation isn’t everything.
I see. That’s a bit of a relief. So, is there any point in sending her to an English conversation school once a week?
Honestly, with exposure of about once a week for 1 hour, dramatic gains are hard to expect, in either sound or grammar. Effects confirmed in research are mostly for much more frequent exposure (every day, a bilingual environment at home, and so on). I don’t deny going to a school, but an expectation of “it’s fine if she enjoys going” may be realistic.
Important factors other than “age”
a recent review paper organizing the effects of age in second language acquisition
names, as factors more important than the age of starting, the quality and quantity of exposure, the distance from the native language, the learner’s motivation, and the social environment.
In other words, it cannot be explained by “at what age one started” alone. For example, a child in Japan who attended an English conversation school once a week and a child who transferred to a school in an English-speaking country and spent every day in an English environment will have very different results, even with the same starting age.
If you are actually going to do it, how should you go about it?
Priorities for what you can do at home
Based on the research, the order looks like this.
- Put the development of the native language (Japanese) first: bilingual education research shows that having a foundation of a “strong native language” in both languages is advantageous for later language development
- Quality over quantity: rather than fragmented exposure to English, “meaningful” contact with English that the child enjoys, such as picture books, songs, and play
- Within the range you can keep up: rather than forcing 30 minutes every day, continuing happily 2-3 times a week is better in the long run
- Don’t expect too much: rather than setting the goal at “speaking like a native,” “removing resistance to English” is enough
Whether to send your child to an English conversation school
Speaking from research, there is not much evidence that a once-a-week English conversation school “dramatically improves English ability.” However, if:
- The child is enjoying it
- It is not a burden on the household budget
- It is not squeezing time for other lessons or play
are met, it has enough meaning as “a starting point for becoming familiar with English.” On the other hand, if these are not met, the research grounds for forcing the child to go are weak.
Closing dialogue
In the end, what should I do? Should I have her do English, or is it fine not to…
Neither is “the right answer.” For telling sounds apart, it’s true that up to about the first year of life is an important period, but other English abilities (vocabulary, grammar, expressiveness, etc.) can be developed over many years from now. If your child is now happily reading Japanese picture books and playing with friends, that’s becoming the best foundation of all.
You mean Japanese is more important?
Rather than “Japanese is more important,” it’s that “solid development of the foundational language also helps the languages learned later.” So there’s no need to cut the time spent reading her picture books in Japanese or listening to her stories for the sake of English. In fact, that is exactly what matters.
Somehow I feel the pressure lifting. Thank you.
Research details
Primary sourcesStudy design: Large-scale online survey (English grammar judgment test)
Participants: 669,498 English speakers (including native speakers and second-language speakers)
Main results: It suggests that the “critical period for starting learning” to achieve complete mastery of grammar is not early childhood, as previously thought, but that high flexibility is maintained until around age 17.4. The age effect is not a sudden “cliff” but a gradual decline.
Limitations: Because it is an online test, it depends on participants’ self-reports. There may be separate age effects for things other than grammar (pronunciation, fluency, etc.).
Study design: A review of brain imaging research on infants and young children
Participants: Infants in various countries (including follow-up data from 6 to 12 months of age)
Main results: Until 6 months of age, babies can distinguish the phonemes of every language in the world, but by 12 months the ability to discriminate phonemes not in the native language declines sharply. While the ability of Japanese infants to tell English L/R apart declines between 8 and 10 months of age, American infants in an English environment improve in the ability to tell the same sounds apart during the same period (Perceptual Narrowing). Early language input affects the specialization of speech-processing circuits.
Limitations: The relationship between phoneme discrimination ability and “actual second-language proficiency” needs separate testing.
Study design: A review paper on age effects in second language acquisition
Scope: An integrated review of existing major studies
Main results: The age of starting is important but not the only determining factor. The amount of exposure, the distance from the native language, motivation, the social environment, and more have combined effects. The concept of a “critical period” is being redefined as different “sensitive periods” for each ability (sound, grammar, vocabulary).
Limitations: Because it is a review paper, it does not provide new empirical data.