PT - JOURNAL ARTICLE AU - Clément François AU - Pablo Ripollés AU - Laura Ferreri AU - Jordi Muchart AU - Joanna Sierpowska AU - Carme Fons AU - Jorgina Solé AU - Monica Rebollo AU - Robert J Zatorre AU - Alfredo Garcia-Alix AU - Laura Bosch AU - Antoni Rodriguez-Fornells TI - RIGHT STRUCTURAL AND FUNCTIONAL REORGANIZATION IN 4-YEAR-OLD CHILDREN WITH PERINATAL ARTERIAL ISCHEMIC STROKE PREDICT LANGUAGE PRODUCTION AID - 10.1523/ENEURO.0447-18.2019 DP - 2019 Aug 05 TA - eneuro PG - ENEURO.0447-18.2019 4099 - http://www.eneuro.org/content/early/2019/08/05/ENEURO.0447-18.2019.short 4100 - http://www.eneuro.org/content/early/2019/08/05/ENEURO.0447-18.2019.full AB - Brain imaging methods have contributed to shed light on the mechanisms of recovery after early brain insult. The assumption that the unaffected right hemisphere can take over language functions after left perinatal stroke is still under debate. Here, we report how patterns of brain structural and functional reorganization were associated with language outcomes in a group of 4-year-old children with left perinatal arterial ischemic stroke. Specifically, we gathered specific fine-grained developmental measures of receptive and productive aspects of language as well as standardized measures of cognitive development. We also collected structural neuroimaging data as well as functional activations during a passive listening story-telling fMRI task and a resting state session (rs-fMRI). Children with a left perinatal stroke showed larger lateralization indices of both structural and functional connectivity of the dorsal language pathway towards the right hemisphere that, in turn, were associated with better language outcomes. Importantly, the pattern of structural asymmetry was significantly more right-lateralized in children with a left perinatal brain insult than in a group of matched healthy controls. These results strongly suggest that early lesions of the left dorsal pathway and the associated perisylvian regions can induce the inter-hemispheric transfer of language functions to right homolog regions. This study provides combined evidence of structural and functional brain reorganization of language networks after early stroke with strong implications for neurobiological models of language development.Significance statement The prevalent theories explaining the functional recovery of language functions after perinatal ischemic stroke strikingly differ on the role of perilesional functionally spared regions as opposed to the homologous non-affected contralesional brain areas. Here, we assessed how patterns of brain functional and structural reorganization were associated with language outcomes in a group of 4-year-old children with left perinatal arterial ischemic stroke. Larger lateralization indices of both functional and structural connectivity towards the right hemisphere were associated with higher levels of language development. Thus, inter-hemispheric plasticity through structural and functional hyper-connectivity mechanisms might be crucial in early damage, probably through the degeneration of neurons projecting from temporal to frontal areas together with contralateral axonal sprouting over the right hemisphere.