Learning A Second Language As An Adult

Becoming fluent in a second language is difficult. But for adults, is it impossible? Science says no. In this encore episode, Short Wave host Emily Kwong https://www.npr.org/people/767284140/emily-kwong dissects the "critical period hypothesis," a theory which linguists have been debating for decades — with the help of Sarah Frances Phillips https://sarahfphillips.com/, a Ph. D. student in the linguistics department at New York University. Together, Emily and former Short Wave host Maddie Sofia https://www.madelinesofia.com/ explore where the theory comes from, how it applies to second-language acquisition and what it means for Emily's efforts to learn Mandarin Chinese as an adult. Have a linguistics or neuroscience question? Email us at [email protected] mailto:[email protected] — we'd love to hear from you! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave http://plus.npr.org/shortwave. See pcm.adswizz.com https://pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. NPR Privacy Policy https://www.npr.org/about-npr/179878450/privacy-policy

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

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• 0:16Speaker 01

  You're listening to Short Wave from NPR.

• 0:21Emily Kwong?

  So, Matty, you and I have known each other for a while now, and I think we're ready to take it to the next level.

• 0:27Speaker 01

  Oh, my God, are we going whitewater rafting?

• 0:29Emily Kwong?

  No.

• 0:29Speaker 01

  Are we doing it?

• 0:30Emily Kwong?

  No, not today. But I have brought you something just as invigorating and just as vulnerable, a Kwong family home movie.

• 0:41Speaker 03

  Yes, I think there's more eggs. Do you see more eggs?

• 0:44Speaker 01

  My baby Kwong.

• 0:47Emily Kwong?

  So I'm two years old, and we're on an Easter egg hunt. I got my floral Easter dress. I got my grandparents, Hui and Edgar Kwong, and they are all about this right now.

• 0:57Speaker 03

  Hey, he has chocolate for you. Oh.

• 1:02Emily Kwong?

  Oh.

• 1:04Speaker 01

  Honestly, you still react that way to chocolate. Let's be real.

• 1:07Emily Kwong?

  It's true.

• 1:07Speaker 03

  Emily, you want an egg?

• 1:09Emily Kwong?

  That's my uncle, Timothy Kwong.

• 1:12Emily Kwong?

  And you'll notice, Matty, throughout these home movies, and I've brought a few today, that there are two languages being spoken by our family, right? There's English, but there's also Mandarin Chinese.

• 1:26Emily Kwong?

  Those are my grandparents during Christmas. But for years, all I could say in Mandarin was hello, thank you, and goodbye. English was the only language I knew.

• 1:45Emily Kwong?

  Qi. Until now. Fan. Qi dian. Qi dian fan. All year, I've been taking Mandarin classes virtually. Oh, no, I got this. Dai. Trying to learn this language. And in the back of my brain, I'm wondering, of course, you know, am I too old to try? Please hold. Tai. Can you really learn another language as an adult? No. I have to say restaurant first, don't I? Right?

• 2:14Speaker 03

  I don't know. What do you think?

• 2:17Speaker 01

  So today in the show, we ask some big questions about second language acquisition and get answers from neuro-linguist Sarah Phillips.

• 2:24Emily Kwong?

  This is Shore Wave from NPR.

• 2:35Speaker 00

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• 3:48Speaker 01

  All right, Emily Kwong, today we are talking about the science of learning a second language, because you are learning Mandarin Chinese, which, like, as far as a hobby goes, more power to you, Emily, more power to you.

• 4:00Emily Kwong?

  Right? For real, though, it is a hard language to learn. Language itself, actually, is an incredible ability, if you think about it, that we humans have. It involves many parts of the brain, and the study of language spans across many different disciplines.

• 4:15Speaker 05

  So bilingualism gets studied in at least three different fields: linguistics, psychology, and cognitive neuroscience.

• 4:24Emily Kwong?

  Sarah Phillips is a PhD student in the linguistics department at New York University, and exactly the person I wanted to call up to talk about language learning.

• 4:33Speaker 01

  Oh, yeah, I remember Sarah from our episode on P600, like, how the brain responds to sentences with confusing grammar or syntax.

• 4:41Emily Kwong?

  Yeah, brains and language are her jam. So her parents met in Korea while her father was serving in the Marine Corps, and they raised her bilingual here in the US.

• 4:52Speaker 05

  Learning Korean was very important to be able to communicate with my mom's side of the family, in the same way that growing up speaking African-American English was very important in being able to communicate and be a part of my dad's side of the family.

• 5:05Emily Kwong?

  She's got a really interesting backstory, and I told her about my project, about taking Mandarin class for two hours every Monday, flashcards on the other nights, watching movies I can't understand, and listen to this.

• 5:20Speaker 05

  Someone who is engaging in learning a second language, thereby uses another language on a pretty regular basis, that means you're a developing bilingual. So in essence, you are a bilingual.

• 5:33Emily Kwong?

  Oh.

• 5:34Speaker 05

  But, you know, we would probably qualify that.

• 5:37Emily Kwong?

  I'm a baby bilingual.

• 5:38Speaker 05

  Exactly, baby bilingual. Maybe as an alternative to baby bilingual, maybe we should think of this as a developing bilingual.

• 5:46Speaker 01

  Oh, that's pretty cool, though. You're a developing baby bilingual.

• 5:48Emily Kwong?

  Mm-hmm. And Sarah says, more specifically, because she's a scientist, that I am a developing sequential bilingual, meaning I'm learning a second language after acquiring a first language. But that's really different from a simultaneous bilingual like Sarah, who developed the ability to speak two or more languages in the earliest years of life. And one of the reasons I never tried to learn my heritage language, honestly, is because of something called the critical period hypothesis. Have you ever heard of this?

• 6:21Speaker 01

  I think so. Is that the idea that you can only become fluent in a language when you're young? Like, there's this critical window for language learning?

• 6:29Emily Kwong?

  Yeah, it's a theory that dates back to the 1950s.

• 6:32Speaker 01

  OK.

• 6:33Emily Kwong?

  And basically argues there's a magic window for a person to learn a first language, somewhere between age two and puberty. Scientists debate the cutoff age, but the key idea is there's a biological window where language learning is the most automatic.

• 6:49Speaker 05

  Where this comes from actually starts really early on with work done with zebra finches, and how zebra finches, and maybe even other types of birds, but the literature that I'm familiar with, points to zebra finches where...

• 7:07Speaker 05

  Early on in their development, they have to learn certain songs or calls that are particular to their kind. And these calls are important for things like mating and, you know, detecting trouble. In essence, they're important for communicating certain things that are important for their communities.

• 7:27Speaker 01

  Hmm, OK.

• 7:29Emily Kwong?

  And Maddie, researchers found that if baby zebra finches were separated from adults for long enough, they couldn't produce the same calls as their parents. Which isn't good, right? When you think about how important these calls are for mating and socialization in zebra finch communities.

• 7:46Speaker 01

  Dang, OK. So does the same thing happen with humans? Like, I don't know that you could ethically study that, but I'm curious.

• 7:52Emily Kwong?

  Well, there have been cases where children were denied language before puberty because of abusive parents or extreme social isolation. And when many of those children tried to learn their first language past puberty, they couldn't pick up the grammar.

• 8:09Speaker 01

  Gotcha, gotcha. OK, but how does this apply to second language acquisition? In your earlier question, like, how late is too late to learn another language?

• 8:18Emily Kwong?

  Yeah, this has been the big question. Because the critical period hypothesis has totally entered our popular consciousness as kind of this rule of second language learning, too. That you can't really learn a language fluently when you're older.

• 8:34Speaker 01

  Right.

• 8:34Emily Kwong?

  And scientists kind of disagree with this. Let's unpack why by looking at the developing baby brain.

• 8:40Speaker 01

  Ooh, neuroscience, we love it.

• 8:42Emily Kwong?

  Mm-hmm, mm-hmm. So little humans experience an explosive amount of language learning in the first few years of life. Our brain cells change over time. And that change is most rapid when we're little.

• 8:54Speaker 01

  Right.

• 8:54Emily Kwong?

  As our bodies produce neurological structures and connections we'll use throughout our lifetime. Researchers at the Center for the Developing Child at Harvard University estimate that in the first three years of life, your brain was developing 1 million new neural connections per second.

• 9:13Speaker 01

  Every second?

• 9:14Emily Kwong?

  Yes.

• 9:15Speaker 01

  That's too many. Take it easy, brain. You know what I mean? That's a lot.

• 9:18Emily Kwong?

  Baby brain's gotta grow. But here's the thing, your brain doesn't stop building neural connections after you're pubescent, right?

• 9:24Speaker 01

  Right, right, right.

• 9:25Emily Kwong?

  And in the 90s and the early 2000s, researchers took note of that. They began to argue that second language learning is not bound to a biological period. How could it be? And this idea emerged that the critical window should actually be called a sensitive window, when you're most susceptible to picking up a new language. Sarah agrees with that.

• 9:45Speaker 05

  When we think about the critical period, we really want to think about this period of time where our brains are going through an explosive amount of growth and change. And so it's easier and even optimal to then want to learn as many things, including languages, during that time period because our brains are so quick and easy to soak up information.

• 10:12Emily Kwong?

  And once you're past that window, like me, you can still become fluent in another language. It will just take way more conscious effort. That's the distinction.

• 10:22Speaker 01

  Not just, like, you're essentially rewiring your brain a little bit.

• 10:25Emily Kwong?

  Yeah, or a lot. And most scientists agree that this process becomes more difficult with age because your body, including your brain, has already developed certain habits. And habits are hard to break.

• 10:36Speaker 05

  If we think about language, like, it's not just our brains involved, right? We also have to use our eyes to perceive what we see. And we use our mouths if we're oral producers of language. You know, we have to finagle our mouths to do the right things, right? And these are all habits that we've developed during our early childhood years. So, once you become an adult, now you have to learn how to break those habits to adopt a new way of speaking and doing. And so it's a little harder, but it's not impossible.

• 11:05Emily Kwong?

  It's very comforting. I hear you that I'm gonna have to fight for it.

• 11:08Speaker 01

  Emily Kwong, you're always fighting for stuff. You're always fighting for stuff. You're a fighter. You got this.

• 11:13Emily Kwong?

  And I'm willing to fight for this one, you know?

• 11:15Speaker 01

  Yeah.

• 11:15Emily Kwong?

  Like, contemporary research shows there are a lot of factors that influence language learning beyond your age. There's education and exposure and the chance to practice in your community.

• 11:28Emily Kwong?

  And I'm not going for total fluency here. I just want to know enough for my relatives to tell me how bad I am. And to be able to say, 我的名字是Emily Kwong. 你吃了吗? Which means, have you eaten? Nice. Thank you. And have you eaten is kind of a common refrain in a lot of Asian languages. It's kind of a way of saying, I love you. Oh, I really love that. That's nice. So Maddie, in response, if you've eaten, you would say, 吃了? 吃了. 很好. Now, one area I'm kind of self-conscious about is pronunciation. So if you're listening, do not come for my tone. I already know, I already know. Mandarin is a tonal language, and some of these tones my mouth has never made before. Right.

• 12:13Emily Kwong?

  And Sarah said, that's an area where childhood speakers have a clear, unmistakable advantage.

• 12:19Speaker 05

  The sound system is really the first things we learn about our languages, right? So the rise and fall and intonation and pitch and those kinds of things, as well as the actual speech sounds of our language. Those are literally some of the first things that we learn in our infancy.

• 12:38Emily Kwong?

  Which is why adults struggle to produce the speech sounds of another language. But when it comes to pronunciation and accents, Sarah kind of pushed back on my questions, asking me, who do you imagine as a perfectly native speaker anyway? Is it fair to compare yourself to that person?

• 12:58Speaker 05

  I'm willing to bet that your lived experiences are going to be dynamically different from the person who you envision as your native speaker. And so you might not ever actually become native-like in your pronunciation, but I don't think that that should be something that people stress over. And the reason being is that the way that we use language fits our identity.

• 13:26Emily Kwong?

  So I can let go of the idea of sounding just like my grandparents, who grew up in Beijing.

• 13:31Speaker 01

  Right.

• 13:31Emily Kwong?

  Because it's here, in the US, among my extended family and other Chinese Americans, that I long to be understood.

• 13:40Speaker 05

  Are you saying it well enough to be understood? That should be really the threshold upon which you want to cross.

• 13:47Speaker 01

  Oh, my gosh. I love that. That's so comforting. Like, this is like language therapy right now, like, learning a new language therapy. Because everybody worries about that, pronunciation, when they're trying to speak in a different language, right?

• 13:58Emily Kwong?

  Yeah, it took the pressure off enormously. And I should share with you, my grandma was trying to teach me Mandarin in the years before she and my grandfather died.

• 14:10Speaker 06

  Have you guys had some breakfast? Wangji ni chil mei ya? Qiu shi wo ge zhi di da ni de chen.

• 14:17Emily Kwong?

  So I feel like I kind of owe it to them to try. Nai nai, wo qi le, xie xie.

• 14:30Speaker 01

  Emily, thank you so much for bringing us a story that's as personal as it gets. Your heritage, your family, your brain chemistry. Thank you.

• 14:38Emily Kwong?

  Thank you, Matty.

• 14:43Speaker 01

  Today's episode was produced by Thomas Lu, edited by Viet Le, and fact-checked by Indy Kara. The audio engineer for this episode was Alex Striewenskis.

• 14:52Emily Kwong?

  Special thanks to sociolinguist Amelia Sang, Fluent City Language School, Dennis Yue Yolli, Megan Arias, and my family, especially Christopher Kwong, Timothy Kwong, Linda Kwong, and Amanda Kwong.

• 15:07Speaker 01

  This is Short Wave, from NPR.

• 15:16Speaker 00

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