Intervention-induced cortical thickness changes in Chinese children with reading disability

Prior research has documented reading improvement and brain changes following intervention in children with reading disability (RD). It remains unclear, however, how specific the brain changes are to different interventions and how SES interacts with different reading interventions in influencing reading improvement. Sixty-seven Chinese children with RD were randomly assigned to a phonological intervention group (PI, N = 24), a morphological intervention group (MI, N = 21), and a waitlist group (WL, N = 22). We found that both interventions effectively improved reading, and the PI improved phonological awareness while the MI improved morphological awareness additionally. In the brain, we found intervention-specific effect in cortical thickening with the right middle/superior temporal gyri for the PI and the left inferior occipital gyrus, superior parietal lobule and inferior frontal gyrus for the MI, suggesting different neural mechanisms underlying different interventions. Furthermore, lower SES was correlated with greater reading improvement and greater cortical thickening in the right MTG only in the PI group. Our findings suggest specific neurocognitive mechanisms underlying phonological and morphological intervention in Chinese RD, and SES has a greater influence on the responsiveness to the phonological intervention than the morphological intervention, which may be because phonological skills are more environment dependent than morphological skills.