Researchers are exploring the possibility that children learn large groups of words rapidly through an automatic "data-mining" process. Conventional thinking says that vocabulary is built one word at a time. Findings from this research challenge that conventional thinking.
In one of their studies, published in the journal Cognition, Yu and Smith attempted to teach 28 12- to 14-month-olds six words by showing them two objects at a time on a computer monitor while two pre-recorded words were read to them. No information was given regarding which word went with which image. After viewing various combinations of words and images, however, the children were surprisingly successful at figuring out which word went with which picture.
In the adult version of the study, which used the same eye-tracking technology used in the Cognition study, adults were taught 18 words in just six minutes. Instead of viewing two images at a time, they simultaneously were shown anywhere from three to four, while hearing the same number of words. The adults, like the children, learned significantly more than would be expected by chance. Many of the adult subjects indicated they were certain they had learned nothing and were "amazed" by their success. Yu and Smith wrote in the journal Psychological Science, "This suggests that cross-situational learning may go forward non-strategically and automatically, steadily building a reliable lexicon."
I wonder if findings from the adult study explain why intense immersion seems to be required for most adults to attain second language fluency? Could it be that we need the very rich data pool provided by immersion, along with relative isolation from our first language, to get the unconscious data-mining process to kick-in?