Development of syntactic processing was examined to evaluate maturational processes including left language lateralization functions and increased specialization of brain regions important for syntactic processing. We utilized multimodal methods, including indices of brain activity from fMRI during a syntactic processing task, cortical thickness measurements from structural MRI, and neuropsychological measures. To evaluate hypotheses about increasing lateralization and specialization with development, we examined relationships between cortical thickness and magnitude and spatial activation extent within the left inferior frontal gyrus (IFG) and its right hemisphere homologue. We predicted that increased activation in the left and decreased activation in the right IFG would be associated with increased syntactic proficiency. As predicted, a more mature pattern of increased thickness in the right pars triangularis was associated with decreased activation intensity and extent in the right IFG. These findings suggest a maturational shift towards decreased involvement of the right IFG for syntactic processing. Better syntactic skills were associated with increased activation in the left IFG independent from age, suggesting increased specialization of the left IFG with increased proficiency. Overall, our findings show relationships between structural and functional neurodevelopment that co-occur with improved syntactic processing in critical language regions of the IFG in typically developing children.
Bibliographical noteFunding Information:
This research was supported by the following organizations: National Institute of Child Health and Human Development ( R01 HD053893 ), National Institute on Drug Abuse ( R01 DA017831 ), National Institutes of Alcoholism and Alcohol Abuse ( U01 AA017122 ), National Center for Research Resources ( U54 RR021813 ), and March of Dimes ( 6-FY2008-50 ). Portions of the analysis were also conducted using the UCLA Laboratory of Neuro Imaging Pipeline processing environment. The authors report no conflicts of interest.
- Typical development
ASJC Scopus subject areas
- Cognitive Neuroscience