Learning a second language (L2) is becoming increasingly important given the globalization of modern life. Yet, L2 learning is notoriously difficult, especially in adulthood, and even after high proficiency is reached, learners face the difficult yet critical task of retaining what they have learned. We currently know very little about the neural mechanisms underlying L2 acquisition and retention. A major roadblock in investigating the neurocognitive trajectory of L2 acquisition is the time it takes a learner to acquire a full language, from initial exposure all the way to high proficiency. With support from the National Science Foundation, Dr. Michael Ullman and colleagues will use a new approach to reveal the neural processing involved in the entire trajectory from initial acquisition to high proficiency and then subsequent retention. Using a reduced version of an actual natural language, Basque, but with many fewer words and a simplified grammar, learners can achieve high proficiency in a relatively shorter time. Investigating L2 learning using this reduced language may offer insights into shared neural mechanisms underlying the learning and retention of a full language. Both behavioral and functional Magnetic Resonance Imaging (fMRI) measures will be continuously recorded while English-speaking adults learn reduced Basque to high proficiency, over several learning sessions spread out over several days, as well as again one and six months later to examine language retention. This study will provide the first fine-grained picture of the full behavioral and neural trajectories of L2 learning from initial exposure to high proficiency and then retention.
Understanding how the brain learns a second language to high proficiency, and then retains it, will pave the way to multiple beneficial outcomes. First, it may lead to effective evidence-based language learning and teaching approaches. For example, different neurocognitive mechanisms could be targeted for different aspects of language at different points in the learning trajectory. Such approaches could have significant impacts for education, security, and the economy, where learning an L2 is often important, and sometimes critical. Such approaches could also lead to advances in language (re)learning therapies for individuals with developmental or acquired disorders (e.g., Specific Language Impairment, dyslexia, autism, acquired aphasias), with substantial clinical benefits. The proposed research may additionally impact research methodology, since demonstrating the utility of this paradigm would open up major new avenues of L2 research. The project should also have institutional and educational benefits. It brings together researchers from several disciplines and institutions, strengthening existing collaborations and forming new ones. Finally, the project will be leveraged to train the next generation of scientists, through the development of an undergraduate research module, and the training of high school, graduate, and post-doctoral students, providing them with first-hand experience in cutting edge interdisciplinary research.
