A new study shows that an infant’s brain reprocesses what it has learned and creates new knowledge even during sleep.
Babies from 9 to 16 months of age remember the names of objects better if they had a short nap, researchers from the University of Tübingen and the Max Planck Institute for Human Cognitive and Brain Sciences in the city of Leipzig, both in Germany, said in a study.
The sleeping baby’s brain converts new experience into knowledge, the study noted.
When waking from a nap, infants can then transfer learned names to similar new objects.
Researchers believe that the brain retrieves recent experiences when asleep, thereby integrating new knowledge into the existing memory. This is done by strengthening, re-linking or even dismantling neuronal connections.
When the brain is largely cut off from outside influences, as in sleep, it organizes its experiences and forms new generalizations.
“In this way, sleep bridges the gap between specific objects and general categories, thus transferring experience into knowledge," explained Manuela Friedrich of the Max Planck Institute for Human Cognitive and Brain Sciences.
The study was conducted on a group of babies who were repeatedly shown images of certain objects while hearing the fictitious names assigned to the objects.
One group of infants took a nap for up to two-hours while the other group remained awake.
The children who had stayed awake had forgotten the names of the individual objects. The group who took a nap remembered a series of object-word mappings.
Scientists also found radical differences in their abilities to categorize the objects.
“The infants who slept after the training session assigned new objects to the names of similar-looking objects… They were not able to do that before their nap, and nor were the ones who stayed awake able to do it. This means that the categories must have been formed during sleep,” Friederici concluded.