Elizabeth R. Sowell

Bio: Elizabeth R. Sowell is an academic researcher from University of Southern California. The author has contributed to research in topics: Fetal alcohol syndrome & Population. The author has an hindex of 67, co-authored 161 publications receiving 22000 citations. Previous affiliations of Elizabeth R. Sowell include University of California, San Diego & Boston Children's Hospital.

Mapping cortical change across the human life span

Abstract: We used magnetic resonance imaging and cortical matching algorithms to map gray matter density (GMD) in 176 normal individuals ranging in age from 7 to 87 years. We found a significant, nonlinear decline in GMD with age, which was most rapid between 7 and about 60 years, over dorsal frontal and parietal association cortices on both the lateral and interhemispheric surfaces. Age effects were inverted in the left posterior temporal region, where GMD gain continued up to age 30 and then rapidly declined. The trajectory of maturational and aging effects varied considerably over the cortex. Visual, auditory and limbic cortices, which are known to myelinate early, showed a more linear pattern of aging than the frontal and parietal neocortices, which continue myelination into adulthood. Our findings also indicate that the posterior temporal cortices, primarily in the left hemisphere, which typically support language functions, have a more protracted course of maturation than any other cortical region.

Longitudinal Mapping of Cortical Thickness and Brain Growth in Normal Children

Abstract: Recent advances in magnetic resonance imaging (MRI) technology now allow the tracing of developmental changes in the brains of children. We applied computer-matching algorithms and new techniques for measuring cortical thickness (in millimeters) to the structural MRI images of 45 children scanned twice (2 yr apart) between the ages 5 and 11. Changes in brain size were also assessed, showing local brain growth progressing at a rate of ∼0.4-1.5 mm per year, most prominently in frontal and occipital regions. Estimated cortical thickness ranged from 1.5 mm in occipital regions to 5.5 mm in dorsomedial frontal cortex. Gray matter thinning coupled with cortical expansion was highly significant in right frontal and bilateral parieto-occipital regions. Significant thickening was restricted to left inferior frontal (Broca's area) and bilateral posterior perisylvian (Wernicke's area on the left) regions. In the left hemisphere, gray matter thickness was correlated with changing cognitive abilities. For the first time, developmental changes in gray matter thickness, brain size, and structure-function relationships have been traced within the same individuals studied longitudinally during a time of rapid cognitive development.

In vivo evidence for post-adolescent brain maturation in frontal and striatal regions.

Abstract: We spatially and temporally mapped brain maturation between adolescence and young adulthood using a whole-brain, voxel-by-voxel statistical analysis of high-resolution structural magnetic resonance images (MRI). The pattern of brain maturation during these years was distinct from earlier development, and was localized to large regions of dorsal, medial and orbital frontal cortex and lenticular nuclei, with relatively little change in any other location. This spatial and temporal pattern agrees with convergent findings from post-mortem studies of brain development and the continued development over this age range of cognitive functions attributed to frontal structures.

Family income, parental education and brain structure in children and adolescents

Abstract: Socioeconomic disparities are associated with differences in cognitive development. The extent to which this translates to disparities in brain structure is unclear. We investigated relationships between socioeconomic factors and brain morphometry, independently of genetic ancestry, among a cohort of 1,099 typically developing individuals between 3 and 20 years of age. Income was logarithmically associated with brain surface area. Among children from lower income families, small differences in income were associated with relatively large differences in surface area, whereas, among children from higher income families, similar income increments were associated with smaller differences in surface area. These relationships were most prominent in regions supporting language, reading, executive functions and spatial skills; surface area mediated socioeconomic differences in certain neurocognitive abilities. These data imply that income relates most strongly to brain structure among the most disadvantaged children.

Mapping Continued Brain Growth and Gray Matter Density Reduction in Dorsal Frontal Cortex: Inverse Relationships during Postadolescent Brain Maturation

Abstract: Recent in vivo structural imaging studies have shown spatial and temporal patterns of brain maturation between childhood, adolescence, and young adulthood that are generally consistent with postmortem studies of cellular maturational events such as increased myelination and synaptic pruning. In this study, we conducted detailed spatial and temporal analyses of growth and gray matter density at the cortical surface of the brain in a group of 35 normally developing children, adolescents, and young adults. To accomplish this, we used high-resolution magnetic resonance imaging and novel computational image analysis techniques. For the first time, in this report we have mapped the continued postadolescent brain growth that occurs primarily in the dorsal aspects of the frontal lobe bilaterally and in the posterior temporo-occipital junction bilaterally. Notably, maps of the spatial distribution of postadolescent cortical gray matter density reduction are highly consistent with maps of the spatial distribution of postadolescent brain growth, showing an inverse relationship between cortical gray matter density reduction and brain growth primarily in the superior frontal regions that control executive cognitive functioning. Inverse relationships are not as robust in the posterior temporo-occipital junction where gray matter density reduction is much less prominent despite late brain growth in these regions between adolescence and adulthood. Overall brain growth is not significant between childhood and adolescence, but close spatial relationships between gray matter density reduction and brain growth are observed in the dorsal parietal and frontal cortex. These results suggest that progressive cellular maturational events, such as increased myelination, may play as prominent a role during the postadolescent years as regressive events, such as synaptic pruning, in determining the ultimate density of mature frontal lobe cortical gray matter.

Principles of Neural Science

Abstract: I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

From Neurons to Neighborhoods: The Science of Early Childhood Development

Abstract: How we raise young children is one of today's most highly personalized and sharply politicized issues, in part because each of us can claim some level of "expertise." The debate has intensified as discoveries about our development-in the womb and in the first months and years-have reached the popular media. How can we use our burgeoning knowledge to assure the well-being of all young children, for their own sake as well as for the sake of our nation? Drawing from new findings, this book presents important conclusions about nature-versus-nurture, the impact of being born into a working family, the effect of politics on programs for children, the costs and benefits of intervention, and other issues. The committee issues a series of challenges to decision makers regarding the quality of child care, issues of racial and ethnic diversity, the integration of children's cognitive and emotional development, and more. Authoritative yet accessible, From Neurons to Neighborhoods presents the evidence about "brain wiring" and how kids learn to speak, think, and regulate their behavior. It examines the effect of the climate-family, child care, community-within which the child grows.