Beyond the language network: Associations between reading, receptive vocabulary, and grey matter volume in 10-year-olds.

Most research on the neurostructural basis of language abilities in children stems from small samples and surface-based measures. To complement and expand the existent knowledge, we investigated associations between grey matter volume and language performance in a large sample of 9-to-11-year-old children, using data from the Adolescent Brain Cognitive Development (ABCD) Study (N = 1865) and an alternative measure of grey matter morphology. We estimated whole-brain grey matter volume for one half of the sample (N = 939) and tested for correlations with scores on a picture vocabulary and a letter and word reading test, with and without factoring in general intelligence and total grey matter volume as additional covariates. The initial analyses yielded correlations between grey matter in the right occipital fusiform gyrus, the right lingual gyrus, and the cerebellum for both vocabulary and reading. Employing the significant clusters from the first analyses as regions of interest in the second half of the cohort (N = 926) in correlational and multiple regression analyses suggests the cluster in the right occipital fusiform and lingual gyri to be most robust. Overall, the amount of variance explained by grey matter volume is limited and factoring in additional covariates paints an inconsistent picture. The present findings reinforce existent doubt with respect to explaining individual differences in reading and vocabulary performance based on unique contributions of macrostructural brain features.