Testverfah - Bundesverband Legasthenie und Dyskalkulie eV

15. Kongress des Bundesverbandes Legasthenie Abstractband
functional MRI (fMRI) studies of reading impairment have demonstrated reduced
functional activity associated with reading in left hemisphere regions such as the
mid-temporal and left fusiform gyrus. Furthermore, adult Diffusion Tensor Imaging
(DTI) studies have demonstrated that reading disability correlates with white matter
integrity within left hemisphere regions, including superior-inferior fibers at the level
of the cingulum (Klingberg, 2000; Beaulieu, 2005). We examine the possibility that
such relationships are present in childhood, during the early school years when
reading disability first emerges in a stable fashion. Results demonstrate significant
correlations between children’s standardized reading scores and Fractional Anisotropy
(FA) scores extracted from two anatomically defined regions of interest near the
left perisylvian cortical regions including the arcuate fasiculus and superior-inferior
white matter tracts at the level of the cingulum. Furthermore, these same subjects
participated in an fMRI study contrasting BOLD responses during a reading task
versus a resting condition. Similar to previous findings in adults, children as a group
demonstrated significant reading-related increases in BOLD responses within left
mid-temporal and left basal-temporal regions, as well as within frontal regions. To
investigate potential relationships between individual differences in white matter
tract development and functional activation during the reading task, we examined
BOLD responses within two regions of interest implicated in the current and previous
reading research: left mid-temporal and left fusiform gyrus, as a function of
individual variation in the DTI scores described above. Results showed significant
correlations between fractional anisotropy scores and BOLD responses, suggesting
a potential link between white matter tract development and functional activation of
reading-related regions in children. Finally, I will review findings that demonstrates
that some patterns of functional activation can be significantly impacted by reading
intervention efforts.
Korrespondenzautor: Bruce McCandliss
bdm2001@med.cornell.edu
++1 212 5465837
++1 212 7465755
From quantitative genetics to behavioural genomics: Early reading abilities and
disabilities
*Emma Meaburn (1), Nicole Harlaar (1), Robert Plomin (1)
(1) King’s College London, Institute of Psychiatry, London, Großbritannien
Identifying specific genes for reading disabilities has been an elusive goal despite
research efforts spanning 22 years. We have used quantitative genetic research
on a large sample of twins to guide our molecular genetic research which uses a
systematic association design that provides power to detect quantitative trait loci
(QTLs) of small effect size. Our quantitative genetic analyses, based on 7500 pairs
of 7-year-old twins in the UK Twins Early Development Study (TEDS), have yielded
three main findings: (1) Early reading disabilities are highly heritable; (2) Genes that
influence reading disability also influence normal-range reading abilities; and (3)
There is large overlap between genetic influences on diverse reading processes and
other cognitive processes.
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