Brain mechanisms for reading and language processing in spina bifida meningomyelocele: a combined magnetic source- and structural magnetic resonance imaging study.

OBJECTIVE The development of the ability to process spoken and written language depends upon a network of left hemisphere temporal, parietal, and frontal regions. The present study explored features of brain organization in children with spina bifida meningomyelocele (SBM) and shunted hydrocephalus, who commonly present with precocious development of word reading skills and preservation of vocabulary and grammar skills. METHOD Eight children with SBM were compared with 15 IQ and reading-level matched, typically developing controls on MRI-based morphometric and Magnetic Source Imaging-derived neurophysiological profiles. RESULTS Children with SBM showed reduced magnetic activity in left inferior parietal regions during spoken word recognition and pseudoword reading tasks. We also noted reduced surface area/volume in inferior parietal and posterior temporal regions in SBM and increased gray matter volumes in left middle frontal regions and gyral complexity in left posterior temporal and inferior parietal regions. CONCLUSIONS A complex pattern of changes in cortical morphology and activation may serve as evidence for structural and functional brain reorganization ensuring preservation of language and decoding abilities in children with SBM.