Netflix’s Babies: First Words – Tuning the Ear and Training the Tongue

I think everyone who works in the field of teaching a foreign language is familiar with the silent period hypothesis introduced by Krashen (1982). Recently, I watched a Netflix documentary that provided an interesting ideas that might help explain why this silent period occurs.

One of the key ideas presented was that “the speech circuit of humans is a motor circuit, a set of neurons in the brain that then control muscles, and that's what’s controlling your speech” (Netflix, 2020, 42:15–42:25). This means learning to speak is comparable to training a muscle or developing a new kind of movement – it requires practice and neurological adaptation.

The documentary also explored how children manage to recognize and distinguish individual words, especially since adults speak in connected speech where words flow seamlessly together. One researcher – Jenny Saffran – suggested that children’s brains operate on a statistical level, detecting how frequently different combinations of sounds and syllables appear in the speech they hear. Over time, they begin to recognize which sound combinations commonly occur together in their language and which do not, allowing them to segment the speech stream into meaningful words (Netflix, 2020).

All of this helps explain why it takes time for children to start speaking a language. Whether it is a baby learning a first language or a child learning a second, they often go through a phase of listening before speaking. During this time, they are not just passively absorbing words – they are actively tuning their sound recognition and restructuring their physical ability to produce those new sounds.

And it seems that once the process of tuning the ear and training the tongue is complete, speaking can take off rapidly. I witnessed this with my students – I started teaching them when they were two years old through a total immersion approach, spending all day with the same group of children in kindergarten (about eight hours a day, five days a week). In their first year of learning English, they could barely say anything, but once they started, it was like a snowball effect: their vocabulary exploded seemingly out of nowhere. They began using two- or three-word sentences, which gradually turned into complex sentences, and now, at around five years old, we can have full conversations.

Even though I appreciated the ideas and theories presented in the documentary, I have some critique of one of the experiments mentioned. In the study on children’s ability to recognize frequently occurring sound patterns, the children were exposed to a set of made-up words for only about two minutes before being tested. In my view, such a brief exposure seems too short for new sound patterns to truly settle in a child’s memory. A longer, more natural exposure – over several days, perhaps – might have offered stronger evidence, allowing the words to be absorbed more deeply. While I am not a researcher myself, this part of the experiment felt rushed.

Overall, however, the documentary – in just 50 minutes – offered many compelling ideas. It reminded me how much there still is to discover about language learning, and how insights like these can help us become more thoughtful and effective teachers.

References:

Krashen, S. D. (1982). Principles and practice in second language acquisition. Pergamon Press.

Netflix. (2020, April 17). Babies | First Words | FULL EPISODE | Netflix [Video]. YouTube. https://www.youtube.com/watch?v=BFtbXwnBRg8