When zebra finches learn their songs from their father early in life, their brain is active during sleep.

That is what biologists at Utrecht University conclude in a paper published in the Proceedings of the Royal Society B. Their findings are a further demonstration that birdsong learning is very similar to the way that children learn how to speak.

This discovery has important consequences for our understanding of the brain processes involved in learning and memory. Human infants learning to speak show increased activation in a part of the brain that is comparable to that studied in young zebra finches. Furthermore, language learning in children is improved when they are allowed to take a nap. The Utrecht discovery will increase our understanding of the role of sleep in the formation of memory.

A model for speech learning Previously the researchers, Sharon Gobes, Thijs Zandbergen and Johan Bolhuis, had demonstrated that the way in which zebra finches learn their songs is very similar to the way in which children learn to speak. In both cases learning takes place during early youth and involves considerable practise. Also, in children and songbirds alike, different brain regions are involved in learning and in speaking or singing. The new research shows that, just as in human infants, the brain of the young zebra finch is also active during sleep. This makes songbirds a good animal model to study the role of sleep in human speech acquisition.

The brain is active during sleep It has been known that sleep plays an important role in learning in humans and other mammals. In songbirds it had been shown previously that during sleep the brain has the same pattern of activity as during singing the day before. The present findings show that the more young songbirds have learned from their father's song, the more active their brain is during subsequent sleep.