Brain research
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An event-related potential (ERP) experiment was conducted to explore the differences between Chinese-speaking dyslexic children and normal school children in orthographic and phonological processing during Chinese sentence reading. Participants were visually presented with sentences, word-by-word and were asked to judge whether the sentences were semantically acceptable. The crucial manipulation was on the sentence-final two-character compound words, which were either correct or incorrect. ⋯ In contrast, the dyslexic children in general showed no differences between experimental conditions for P200 and N400, although the more detailed time course analyses did reveal some weak effects for the N400 component between experimental conditions. In addition, the mean amplitude of N400 in the homophonic condition was less negative-going for the dyslexics than for the controls. These findings suggest that Chinese dyslexic children have deficits in processing orthographic and phonological information conveyed by characters and, compared with normal children, they rely more on phonological information to access lexical semantics in sentence reading.
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Intrauterine growth restriction (IUGR) can increase susceptibility to perinatal hypoxic brain injury for reasons that are unknown. Previous studies of the neonatal IUGR brain have suggested that the cerebral mitochondrial capacity is reduced but the glycolytic capacity increased relative to normal weight (NW) neonates. In view of these two factors, we hypothesized that the generation of brain lactate during a mild hypoxic insult would be greater in neonatal IUGR piglets compared to NW piglets. ⋯ ADCs in the high lactate IUGR piglets were significantly lower during hypoxia than in all the other piglets. This signifies increased diffusion of water into brain cells during hypoxia, possibly in response to increased intracellular osmolality caused by high intracellular lactate concentrations. These findings support previous studies showing increased susceptibility to hypoxic brain injury in IUGR neonates but suggest that increased glycolysis during hypoxia confers neuroprotection in some IUGR piglets.