Bruce D. Mccandliss - US grants

Plasticity for speech perception changes during childhood and adolescence, resulting in a sensitive period for second-language acquisition. However, the developmental time-course and the underlying cognitive and neural mechanisms of this change are not adequately understood. The proposed research investigates the hypothesis that entrenchment of native language perception is one mechanism of such age-limited learning. Our specific aims are : 1) Examine the influence of age of arrival on perceptual expertise for second-language speech categories. We will study adult native speakers of Japanese who are learning English using a suite of experimental methods including: a) a visual world task that combines psychophysical measures and sensitive eye-tracking measures, b) a task free dishabituation paradigm for fMRI to study the functional anatomy of phonetic categorization and c) a dishabituation paradigm for EEG that matches the timecourse of the behavioral results and d) productions tasks to assess the relationship between perception and production development. 2) Examine the development of phonetic categorization in children and adolescents applying the methods developed above to native English speakers age 6-18. 3) Explore the relationship between the emergence of native-language expertise and the decline in plasticity for second-language speech categories in the data from Aims 1and 2.We hypothesize that the decline in plasticity during the sensitive period is associated with increasing perceptual expertise. Data collected with the same paradigms and stimuli for adult native speakers of Japanese, native English speaking children, adolescents and adults will be the basis for a strong test of this hypothesis. This investigation will provide insights into the typical developmental timecourse of speech perception from childhood to adulthood, which provides a model system in which to study the cognitive and neural mechanisms behind a basic failure of learning. The normative data, paradigms, and mechanistic insights may ultimately benefit studies of atypical development in clinical populations (i.e. dyslexia, language impairments, and learning disabilities).

How do individual differences in children's brain mechanism for number abilities relate to gains during first grade mathematics, and how might first grade instruction drive changes in such brain mechanisms? These questions are addressed using a battery of brain imaging measures including brain structure (MRI,DTI), bloodflow changes (fMRI), and electrical responses (ERP). Pre-post brain measures track changes over the course of a school year within two groups segregated by a "school's cutoff date" into young first graders and old kindergarteners. This group contrast allows the impact of first grade instruction to be differentiated from maturation and school attendance.

Low math skills significantly limit access to post-secondary education, employment, and lifetime earnings. Because math difficulties can be detected early in schooling, early intervention is key for preventing the negative consequences of persistent low math achievement. Kindergarten is a particularly important developmental time-window within which to intervene given that children who enter and exit kindergarten with low math knowledge are at high risk for having long-term difficulties in mathematics. Many kindergarten children who do not respond adequately to classroom math instruction are characterized as having both low math knowledge and difficulties in focusing and sustaining attention. One way to tackle the math learning difficulties of these at-risk kindergarten children, then, might be to create interventions that conjointly address mathematics and attention. The purpose of this project is to test the effects of a novel approach to intervention in which instruction in mathematics and training in attention are combined.

The aim of this study is to determine whether combined intensive attention training and math intervention leads to greater math learning than the same math intervention without attention training. The study will also seek to determine whether the effects of combined training on mathematics are sensitive to the use of quantitative information during attention training. Two hundred and ten children identified as not having made progress in math in the fall semester of kindergarten will be randomly assigned to one of three active intervention conditions in the spring semester: 1) an intensive mathematics intervention; 2) the same mathematics intervention combined with adaptive game-like attention training designed to improve the abilities to focus and sustain attention; or 3) the mathematics intervention combined with similar adaptive attention training, but where the child has to focus on and respond to quantitative information in the games. Multiple measures of math, attention, and attention-related cognitive competencies such as working memory are measured prior to the intervention, immediately following the intervention, and after a one-month follow-up. The study is designed to address ongoing questions regarding whether cognitive training - in this case, when combined with math intervention - holds any promise for improving mathematical learning for young children at high risk for persistent low math achievement.

This award is supported by the EHR Core Research Program (ECR). ECR supports fundamental research in STEM education in critical research areas that are essential, broad and enduring. The ECR program is distinguished by its emphasis on the accumulation of robust evidence to inform efforts to (a) understand, (b) build theory to explain, and (c) suggest interventions (and innovations) to address persistent challenges in STEM interest, education, learning, and participation.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.