Some people say you can learn English just by playing it in the background. But is that true? In a famous study, nine-month-old American babies heard Chinese twelve times. Some babies played with a Chinese speaker. They learned new Chinese sounds.

Other babies watched the same person on video or heard only the audio. They learned nothing. So listen to English you can understand, pay attention, and try to use it yourself.

Can you learn English just by playing it in the background while you cook or drive? A famous 2003 study suggests that even babies cannot learn this way.

Researchers gave nine-month-old American babies twelve sessions of Mandarin Chinese. Some babies played with a live Chinese speaker. They learned to tell apart Chinese sounds almost as well as babies growing up in Taiwan. Other babies watched the same person on video or heard only the audio. They learned nothing.

For adults, the researcher Richard Schmidt argued that we learn what we notice. English that we do not pay attention to may simply become noise. Background listening does have one use. After focused practice, hearing the same sounds again may support learning.

Leave a language playing in the background and you will pick it up, or so the hope goes, since babies seem to learn that way. A well-known experiment points the other way. In 2003, Kuhl and colleagues gave nine-month-old American infants twelve sessions of exposure to Mandarin.

Some infants spent the sessions with a live speaker who read and played with them. They learned to discriminate a Mandarin sound contrast about as well as infants raised in Taiwan. Others saw the same speaker on video or heard only the audio, and they showed no learning at all.

The researchers proposed that social interaction raises attention and motivation, which switches learning on. The study tested infant perception, and adult speaking ability is a different skill. It undercuts the claim that passive exposure is enough.

In adult research, Schmidt's noticing hypothesis holds that learners acquire what they consciously attend to, and studies of vocabulary learning through listening show that only some new words are picked up this way. Background listening keeps a narrow role. In sound-learning experiments, alternating active practice with periods of passive exposure enhanced learning. That makes background audio most useful for reviewing material already studied with full attention.