Abnormal Cortical Thickness and Brain--
Behavior Correlation Patterns in Individuals with Heavy Prenatal Alcohol Exposure
Source: Cerebral Cortex
2008 Jan;18(1):136-144.
Author: Sowell ER, Mattson SN, Kan E, Thompson PM, Riley EP & Toga AW PubMed ID: 17443018
Abstract:
Quantitative magnetic resonance imaging (MRI) studies in children
with fetal alcohol spectrum disorders (FASDs) have shown regional
patterns of dysmorphology, most prominent in parietal and posterior
temporal cortices. Various methods of image analysis have been
employed in these studies, but abnormalities in cortical thickness have
not yet been mapped over the entire cortical surface in individuals
with FASD. Further, relationships between cognitive dysfunction
and cortical thickness measures have not yet been explored. We
applied cortical pattern matching algorithms and techniques for
measuring cortical thickness in millimeters to the structural brain
MRI images of 21 subjects with heavy prenatal alcohol exposure
(8--22 years, mean age 12.6 years), and 21 normally developing
control subjects (8--25 years, mean age 13.5 years). Dissociable
cognitive measures, of verbal recall and visuospatial functioning,
were correlated with cortical thickness, and group by test score
interactions were evaluated for predicting cortical thickness. Significant
cortical thickness excesses of up to 1.2 mm were observed in
the FASD subjects in large areas of bilateral temporal, bilateral inferior
parietal, and right frontal regions. Significant group by test score
interactions were found in right dorsal frontal regions for the verbal
recall measure and in left occipital regions for the visuospatial
measure. These results are consistent with earlier analyses from our
own and other research groups, but for the first time, we show that
cortical thickness is also increased in right lateral frontal regions in
children with prenatal alcohol exposure. Further, the significant
interactions show for the first time that brain--behavior relationships
are altered as a function of heavy prenatal alcohol exposure.