Increased temporal lobe gyrification in preterm children.
ABSTRACT Preterm birth often results in significant learning disability, and previous magnetic resonance imaging (MRI) studies of preterm children have demonstrated reduction in overall cortical tissue with particular vulnerability in the temporal lobe. We measured cortical gyrification in 73 preterm and 33 term control children at 8 years of age and correlated these findings with tests of language ability to determine the associations among preterm birth, neurodevelopment and functional outcome. Preterm children demonstrated significantly increased bilateral temporal lobe gyrification index compared to term controls. Left temporal gyrification index was significantly negatively correlated with left temporal lobe gray matter volume as well as reading recognition scores in the preterm group. Cortical development in the temporal lobe appears to be differentially vulnerable to preterm birth.
- SourceAvailable from: Chiara Nosarti
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- "e l s e v i e r . c o m / l o c a t e / y n i c l the temporal cortex (Kesler et al., 2006). Together these findings suggest widespread disruption to prototypic patterns of cerebral development . "
ABSTRACT: Advances in neonatal medicine have resulted in a larger proportion of preterm-born individuals reaching adulthood. Their increased liability to psychiatric illness and impairments of cognition and behaviour intimate lasting cerebral consequences; however, the central physiological disturbances remain unclear. Of fundamental importance to efficient brain function is the coordination and contextually-relevant recruitment of neural networks. Large-scale distributed networks emerge perinatally and increase in hierarchical complexity through development. Preterm-born individuals exhibit systematic reductions in correlation strength within these networks during infancy. Here, we investigate resting-state functional connectivity in functional magnetic resonance imaging data from 29 very-preterm (VPT)-born adults and 23 term-born controls. Neurocognitive networks were identified with spatial independent component analysis conducted using the Infomax algorithm and employing Icasso procedures to enhance component robustness. Network spatial focus and spectral power were not generally significantly affected by preterm birth. By contrast, Granger-causality analysis of the time courses of network activity revealed widespread reductions in between-network connectivity in the preterm group, particularly along paths including salience-network features. The potential clinical relevance of these Granger-causal measurements was suggested by linear discriminant analysis of topological representations of connection strength, which classified individuals by group with a maximal accuracy of 86%. Functional connections from the striatal salience network to the posterior default mode network informed this classification most powerfully. In the VPT-born group it was additionally found that perinatal factors significantly moderated the relationship between executive function (which was reduced in the VPT-born as compared with the term-born group) and generalised partial directed coherence. Together these findings show that resting-state functional connectivity of preterm-born individuals remains compromised in adulthood; and present consistent evidence that the striatal salience network is preferentially affected. Therapeutic practices directed at strengthening within-network cohesion and fine-tuning between-network inter-relations may have the potential to mitigate the cognitive, behavioural and psychiatric repercussions of preterm birth.01/2014; 4:352-65. DOI:10.1016/j.nicl.2014.01.005
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- "reported in children born preterm (Kesler et al. 2006). Higher gyrification in the temporal lobes, relative to full-term comparison individuals, was negatively correlated with reading abilities in these regions. "
ABSTRACT: The cortex in spina bifida myelomeningocele (SBM) is atypically organized, but it is not known how specific features of atypical cortical organization promote or disrupt cognitive and motor function. Relations of deviant cortical thickness and gyrification with IQ and fine motor dexterity were investigated in 64 individuals with SBM and 26 typically developing (TD) individuals, aged 8-28 years. Cortical thickness and 3D local gyrification index (LGI) were quantified from 33 cortical regions per hemisphere using FreeSurfer. Results replicated previous findings, showing regions of higher and lower cortical thickness and LGI in SBM relative to the TD comparison individuals. Cortical thickness and LGI were negatively associated in most cortical regions, though less consistently in the TD group. Whereas cortical thickness and LGI tended to be negatively associated with IQ and fine motor outcomes in regions that were thicker or more gyrified in SBM, associations tended to be positive in regions that were thinner or less gyrified in SBM. The more deviant the levels of cortical thickness and LGI-whether higher or lower relative to the TD group-the more impaired the IQ and fine motor outcomes, suggesting that these cortical atypicalities in SBM are functionally maladaptive, rather than adaptive.Cerebral Cortex 08/2012; 23(10). DOI:10.1093/cercor/bhs226 · 8.67 Impact Factor
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- "Regional estimates of gyrification are often increased in psychiatric and neurological conditions relative to controls (Jou, Minshew, Keshavan, & Hardan, 2010; Kesler et al., 2006; Oyegbile, Magnotta, O'Leary et al., 2004). However, associations between local gyrification indices and cognitive abilities are sometimes reported as positive (e.g., McIntosh, Moorhead, McKirdy et al., 2009) and other times as negative (e.g., Kesler et al., 2006) depending on the brain area(s) measured and the particular disorder. Therefore, the direction of deviations in cortical morphometry alone does not inform on the functional significance of these changes. "
ABSTRACT: 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. 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. 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. 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.Neuropsychology 05/2011; 25(5):590-601. DOI:10.1037/a0023694 · 3.43 Impact Factor