original: http://www.nature.com/nsu/010308/010308-4.html

brain: Sliced tongue easier to swallow

JOHN WHITFELD

The best way to learn a new language might be to stay at home and swallow it in bite-sized chunks, rather than immersing yourself in a foreign culture. Researchers have found that adults learning an artificial language retain more when words are presented singly than when they hear sentences from the start.

Psychologists Alan Kersten and Julie Earles, of Florida Atlantic University, believe that their results with adults may mirror the way that children learn languages ¹. Children, they suggest, may find it easier than adults to pick up languages because their limited brainpower forces them to break speech into small pieces.

"Children's processing capacity is perfect for learning a language," says Kersten. He adds, however, that it would be premature to draw strong conclusions from this experiment about how children learn languages or how second languages should be taught.

The two researchers tried to teach undergraduate volunteers to speak the made-up language of the fictional planet 'Betruzi'. Not an expressive tongue, Betruzian consists of only six words describing two related alternatives for a native's appearance, manner of motion and direction of motion. "We were trying to give the learners as much help as we could," says Kersten.

Subjects watched a computer animation of life on Betruzi while hearing it described in a three-word sentence. Some people heard the whole sentence throughout the experiment. The others heard only one word for the first third of the trial, after which a second was added, with the full sentence being spoken only during the last third of the trial.

The students were then tested on another animation, and asked to judge which of two Betruzian sentences most accurately described the new scene. Those who had picked up Betruzian one word at a time matched language to animations better than those who had listened to the whole sentence throughout the test — despite the one-at-a-timers having heard a smaller total amount of speech.

"My view is that starting small is helpful for some aspects of language learning, such as comprehension," says David Plaut, a psychologist and computer scientist at Carnegie Mellon University in Pittsburgh, who has found that 'connectionist' computer networks learn a language better if presented with its full complexity from the outset. "But acquiring grammatical knowledge is better done through exposure to the full language."

Children are thrown in at the deep end of language from the outset, and yet they seem to have no trouble learning several languages at once. Only being able to grasp small chunks of speech may make it easier for them to learn the meanings of individual units of language, rather than associating whole sentences with a single meaning. It may also be easier for them to recombine these units into novel building-blocks.

But Gary Marcus, a psychologist at New York University, points out that near-teenage migrants can pick up new languages with ease, despite their advanced mental development. "The differences in memory abilities between the 12-year-old who masters a new language and the 15-year-old brother who never fully succeeds just seem too slight to explain what's going on," he says.

Wolfgang Klein, who studies language acquisition at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, suspects that adults have a hard time learning languages because their learning skills are generally poorer and because they are less motivated than youngsters. From his studies of migrant workers in Europe, he also believes that a mixture of immersion and teaching is probably the most effective way to pick up another tongue — although, he adds "there's no one uniform method".

1. Kersten, A. W. & Earles, J. L. Less really is more for adults learning a miniature artificial language. Journal of Memory and Language 44, 250–273 (2001).