Neuroanatomy of developmental dyslexia: Pitfalls and promise

@article{Ramus2018NeuroanatomyOD,
  title={Neuroanatomy of developmental dyslexia: Pitfalls and promise},
  author={F. Ramus and Irene Altarelli and Katarzyna Jednor{\'o}g and Jingjing Zhao and Lou Scotto di Covella},
  journal={Neuroscience \& Biobehavioral Reviews},
  year={2018},
  volume={84},
  pages={434-452}
}
HighlightsIn voxel‐based morphometry studies, the larger the sample size, the fewer the number of group differences reported.The literature consists of mostly small‐scale studies, whose results are likely to be inflated or false positive.Most published results show little or no replication across independent studies.The only group difference that is robustly replicated is a smaller brain volume in dyslexic individuals (d = 0.4).Higher methodological standards are necessary to discover true… Expand
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References

SHOWING 1-10 OF 274 REFERENCES
Reduced Brain Size and Gyrification in the Brains of Dyslexic Patients
TLDR
One of the reported neuropathologic findings in dyslexia, that is, wider minicolumns, is expanded, to suggest the decreased gyrification and preserved cortical thickness can alter the information processing capacity of the brain by providing a greater degree of cortical integration at the expense of a slower response time. Expand
Cognitive subtypes of dyslexia are characterized by distinct patterns of grey matter volume
TLDR
VBM is applied to study grey matter volume differences in a relatively large sample of dyslexic children split into three subtypes based on the cognitive deficits: phonological, rapid naming, magnocellular/dorsal, and auditory attention shifting to indicate that dyslexia may result from distinct cognitive impairments characterized by distinguishable anatomical markers. Expand
Planum temporale asymmetry in developmental dyslexia: Revisiting an old question
TLDR
An altered pattern of asymmetry of the planum temporale surface area in dyslexic boys only is revealed, with a greater proportion of rightward asymmetrical cases among dyslexi boys compared to control boys, and the importance of taking gender into account in studies of developmental dyslexia is stressed. Expand
Neuroanatomical anomalies of dyslexia: Disambiguating the effects of disorder, performance, and maturation
TLDR
This is the first study to disambiguate maturational stage on neuroanatomical anomalies of dyslexia in addition to the effects of disorder, reading performance and maturations on neuroinferiority, despite the limitation of a relatively small sample-size. Expand
A qualitative and quantitative review of diffusion tensor imaging studies in reading and dyslexia
TLDR
A quantitative activation likelihood estimation (ALE) meta-analysis on all reported studies that used a voxel-based approach reveals a cluster located close to the left temporoparietal region that demonstrates that this region hosts both the left arcuate fasciculus and the left corona radiata. Expand
Structural MRI studies of language function in the undamaged brain
TLDR
This review paper focuses on structural imaging studies of language that have utilised behavioural measures in order to investigate the neural correlates of language skills in the undamaged brain and highlights the validity of the findings by comparing the results to those from functional imaging studies. Expand
When all hypotheses are right: A multifocal account of dyslexia
TLDR
The data put forward the idea of a multifocal brain abnormalities in dyslexia with a major implication of the left superior temporal gyrus, occipital‐temporal cortices, and lateral/medial cerebellum, which could account for the diverse deficits predicted by the different theories. Expand
Cerebellar Volume and Cerebellar Metabolic Characteristics in Adults with Dyslexia
TLDR
Although it is difficult to interpret the volumetric and spectroscopic results unambiguously, taken together they suggest two possible interpretations: excessive connectivity or abnormal myelination. Expand
Brain classification reveals the right cerebellum as the best biomarker of dyslexia
TLDR
These results provide evidence for the existence of various subtypes of dyslexia characterized by different brain phenotypes, and behavioural analyses suggest that these brain phenotype relate to different deficits of automatization of language-based processes such as grapheme/phoneme correspondence and/or rapid access to lexicon entries. Expand
Machine learning and dyslexia: Classification of individual structural neuro-imaging scans of students with and without dyslexia
TLDR
Data indicate that the LOFG, ROFG and the LIPL are neuro-endophenotype and potentially biomarkers for types of dyslexia related to reading, spelling and phonology and support for the use of machine learning in anatomical brain imaging. Expand
...
1
2
3
4
5
...