"In the absence of language specific cues, words in both of the second language speaker's languages compete for selection well into the process of lexicalizing concepts into spoken words," Kroll told attendees at the Second Language Research Forum today (Oct. 18) in Tucson, Ariz.
Kroll, working with Gretchen Sunderman, Natasha Miller, Natasha Tokowicz and Erica Michael, all recent Penn State graduate students, together with colleagues in the Netherlands, devised a method for testing bilingual speakers that demonstrated that both languages are active at once. Because the researchers could not suppress one language or the other, they set up a test where both languages would be active, and then either the first or second language would be spoken.
Using test subjects who were native Dutch speakers with great proficiency in their second language, English, the researchers presented pictures of objects that were to be identified. The subjects did not initially know which language they would be asked to use to identify the picture, so words in both languages would naturally be active. The researchers then sounded a tone, a high tone for Dutch and a low tone for English, telling the subjects to speak the word in that language.
"If we cannot prevent ourselves from having both languages available simultaneously, then we cannot devise a means for suppressing one language," Kroll says. "Instead, we forced the subjects to think about them both at the same time and compared their performance when asked to name the object only in their first or second language."
In the one language only condition, the researchers performed the experiment with a high tone indicating Dutch and a low tone indicating no response. For an added twist, Kroll and colleagues included pictures in the experiments whose names were cognates -- words that sound similar in both languages -- to see if the similarity made it easier to choose the second language word. "Bilinguals were faster to name cognates, and the result held for the second language even when they were not forced to have the first language active," says Kroll.
The results of these studies indicate that while a second language may not intrude when a bilingual person is speaking their native language, when speaking a second language, the first language is always active and cannot be suppressed.
"A bilingual learns to attend to a set of cues that allows them to suppress the stream of language, to modulate processing so that the second language is what is spoken, but the first language is still there and active," says Kroll. "We would like to understand how that happens."
According to the Penn State researcher, it was thought that an environment of total immersion in a language would provide massive exposure to a second language and suppress the first language. However, she believes that a large component of language immersion involved learning a new set of cues to the second language. To test this, the researchers took students who had no exposure to German or Dutch and taught them a list of 40 Dutch words. Some students learned the words in association with their English counterparts and others learned the words in association with a picture. Some of the pictures were oriented in the normal way and others were upside down or otherwise skewed.
"People who learned the Dutch in association with an object that was oriented uniquely were faster to later translate English words into Dutch," Kroll says. "The misoriented pictures served as a unique cue."
According to Kroll, a basic cognitive principle is that we use what we know to apply old to the new, but she has shown that if a unique cue is provided, an upside down picture or a different environment, it may be an effective way to suppress the native language. "This suggests that people are sensitive to subtle environmental cues and language," says the Penn State researcher. "It provides a clue to the cognitive basis of learning a second language."