1) What is cognitive control? How does bi- or multilingualism affect this?
Cognitive control is the ability to focus your cognitive processes based on particular task demands. For example, if a task demands planning, you can organize your thoughts in a sequential way or if a task demands focusing your attention and ignoring other things, you can do that. It is your ability to focus your attention on things that are relevant to solving a problem and ignore irrelevant details.
It turns out that bilinguals are better at several of these kinds of tasks that involve focusing your attention. Scientists like Judith Kroll and Ellen Bialystock try to make sense of this based on 2 factors: If you are bilingual, then hearing either language automatically triggers the processing systems for both languages. That's the automatic part. So speaking or understanding for a bilingual means constantly focusing attention on whatever language is required in the situation and suppressing the automatically activated signal from the language not currently being spoken. Under this interpretation, its not surprising that they are also better at controlling what they are attending to in other situations ; like focusing on color and ignoring location when the situation requires it.
2) How are scientists currently identifying adults who excel at foreign languages? How has this evolved over time? There are some factors that are associated with reaching high levels of language learning.
First of all, it is very expensive to train second language learners, especially adults!
So we need to be sure that the people we are identifying to be trained are going to do well. My organization, the University of Maryland Center for Advanced Study of Language (CASL) has identified some cognitive factors that can help us identify adults who will excel in foreign languages. We can identify adults who probably would be good at learning a second language by asking questions such as:
These tasks have been assembled into a battery of tests that we call the high level aptitude battery. (HI Lab). This has evolved as our ability to build models of cognitive processing to test against specific behavioral tasks has evolved. The second piece of the puzzle is the development of quantifiable metrics of what we mean by “excelling at foreign language” You have to be able to say what you have to be able to do before we say you ‘excel. Then you can measure the effect of cognitive differences on the ability to perform at a certain level of proficiency.
3) What drew you to study linguistics?
I fell into the field. I started as a philosophy major and became interested in how we learned things. I read Descartes, and became interested in the notion that we are born with constraints that shape the way we see the world. Linguistics added the ability to look at claims like this and to attack them in a testable and precise way. Because I studied at MIT, I was also exposed to computer modeling techniques which allowed you to test hypotheses before you brought subjects into a lab and I was able to use what I learned about language processing to develop useful automatic systems to perform language task. The need to work with researchers with theoretical, experimental, and computational skill sets is what makes things interesting where I work. Sharing knowledge with people who have different skills set, makes for a very exciting environment – we've tried to create that both at CASL and more generally at the University of Maryland.
4) What are the next steps for your research?
CASL's research is multifaceted. One of the areas we are exploring is to see whether some of the cognitive components I talked about earlier as important for language learning can be improved with instruction. For example, people used to believe that once a person reached adulthood your working memory capacity was fixed, but our recent research has shown that subjects can improve their working memory capacity after undergoing a 20 hour training regimen, that this improvement extends to untrained tasks, and improvement lasts after a 3 month hiatus.
The second direction is to demonstrate that individualizing training to target the specific cognitive components that our tests show are deficient in a particular student will improve that student's ability to reach their goals.
We are also making strides in identifying the neural markers for these individual abilities.