In this very interesting study from Washington University St Louis, Schlaggar and his group find that children use action and movement-related areas of the brain to generate words. This is a nifty study because the investigators matched children and adults who showed an equivalent performance. So we are really seeing how kids (age 7-10) use their brains differently from young adults. The word generation trials involved several different ways to generate words - matching verbs with nouns (car & drive), rhymes (cat-hat), and opposites (up-down).
What you can see is that adults (red) tended to use their 'classic' left hemispheric language area to generate words, while kids (blue) were using their right occipitotemporal region, a region involved in multisensory imagery for action and movement. So it seems children are closer to the 'source', associating words with direct sensations and imagery, while adults have gone on to file word knowledge away in their word definition library.
Children, Word Generation, and fMRI
Action Imagery in the Brain