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Synergistic Effects of Age on Patterns of White and Gray Matter Volume across Childhood and Adolescence(1,2,3).

Bray S, Krongold M, Cooper C, Lebel C - eNeuro (2015)

Bottom Line: Linear effects of age on white and gray matter volume were modeled within four age bins, spanning 4-18 years, each including 90 participants (45 male).Four white matter clusters were identified, each with a dominant direction of underlying fibers: anterior-posterior, left-right, and two clusters with superior-inferior directions.Pairs of gray and white matter clusters followed parallel slope trajectories, with white matter changes generally positive from 8 years onward (indicating volume increases) and gray matter negative (decreases).

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Radiology, Cumming School of Medicine, University of Calgary , Calgary, Alberta, Canada T2N 1N4 ; Department of Pediatrics, Cumming School of Medicine, University of Calgary , Calgary, Alberta, Canada T2N 1N4 ; Child and Adolescent Imaging Research Program, Alberta Children's Hospital , Calgary, Alberta, Canada T3B 6A8 ; Alberta Children's Hospital Research Institute , Calgary, Alberta, Canada T3B 6A8.

ABSTRACT
The human brain develops with a nonlinear contraction of gray matter across late childhood and adolescence with a concomitant increase in white matter volume. Across the adult population, properties of cortical gray matter covary within networks that may represent organizational units for development and degeneration. Although gray matter covariance may be strongest within structurally connected networks, the relationship to volume changes in white matter remains poorly characterized. In the present study we examined age-related trends in white and gray matter volume using T1-weighted MR images from 360 human participants from the NIH MRI study of Normal Brain Development. Images were processed through a voxel-based morphometry pipeline. Linear effects of age on white and gray matter volume were modeled within four age bins, spanning 4-18 years, each including 90 participants (45 male). White and gray matter age-slope maps were separately entered into k-means clustering to identify regions with similar age-related variability across the four age bins. Four white matter clusters were identified, each with a dominant direction of underlying fibers: anterior-posterior, left-right, and two clusters with superior-inferior directions. Corresponding, spatially proximal, gray matter clusters encompassed largely cerebellar, fronto-insular, posterior, and sensorimotor regions, respectively. Pairs of gray and white matter clusters followed parallel slope trajectories, with white matter changes generally positive from 8 years onward (indicating volume increases) and gray matter negative (decreases). As developmental disorders likely target networks rather than individual regions, characterizing typical coordination of white and gray matter development can provide a normative benchmark for understanding atypical development.

No MeSH data available.


Related in: MedlinePlus

Preferred white matter direction in each cluster. For this analysis, the voxels within each cluster were thresholded to only those voxels with an eigenvalue ≥0.4 in one of the three canonical directions. a, Shows the proportion of voxels for the maximum value in each direction. b, Illustrates eigenvalues for all three directions across all voxels with at least one eigenvalue ≥0.4, sorted by maximum value in each row (i.e., each row is one voxel; heat map indicates the eigenvalue at that voxel for each canonical direction). SCR, superior corona radiata; CC, corpus callosum; FO, fronto-occipital; AP, anterior–posterior; LR, left–right; SI, superior–inferior.
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Figure 5: Preferred white matter direction in each cluster. For this analysis, the voxels within each cluster were thresholded to only those voxels with an eigenvalue ≥0.4 in one of the three canonical directions. a, Shows the proportion of voxels for the maximum value in each direction. b, Illustrates eigenvalues for all three directions across all voxels with at least one eigenvalue ≥0.4, sorted by maximum value in each row (i.e., each row is one voxel; heat map indicates the eigenvalue at that voxel for each canonical direction). SCR, superior corona radiata; CC, corpus callosum; FO, fronto-occipital; AP, anterior–posterior; LR, left–right; SI, superior–inferior.

Mentions: One white matter cluster included the superior longitudinal fasciculus, superior corona radiata, and body of the corpus callosum (Fig. 1A,C,D), as well as a region along the posterior thalamic radiation (Fig. 1C). White matter voxels were predominantly (68%; Fig. 5) superior–inferior in orientation (Fig. 5). The most spatially similar gray matter cluster included primarily posterior cortical regions (Fig. 1A-D) such as the precuneus (Fig. 1B) and bilateral intraparietal sulcus (Fig. 1C). This cluster also included anterior temporal cortex (Fig. 1A) and smaller bilateral regions of posterior middle frontal gyrus (Fig. 1D). The gray matter cluster was characterized by a steep negative slope in the 8-10.5 year age bin and more positive slopes in other age groups; white matter age slopes followed a similar trend, though slopes were generally positive (indicating increasing volume with age; Fig. 1E-F).


Synergistic Effects of Age on Patterns of White and Gray Matter Volume across Childhood and Adolescence(1,2,3).

Bray S, Krongold M, Cooper C, Lebel C - eNeuro (2015)

Preferred white matter direction in each cluster. For this analysis, the voxels within each cluster were thresholded to only those voxels with an eigenvalue ≥0.4 in one of the three canonical directions. a, Shows the proportion of voxels for the maximum value in each direction. b, Illustrates eigenvalues for all three directions across all voxels with at least one eigenvalue ≥0.4, sorted by maximum value in each row (i.e., each row is one voxel; heat map indicates the eigenvalue at that voxel for each canonical direction). SCR, superior corona radiata; CC, corpus callosum; FO, fronto-occipital; AP, anterior–posterior; LR, left–right; SI, superior–inferior.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4596017&req=5

Figure 5: Preferred white matter direction in each cluster. For this analysis, the voxels within each cluster were thresholded to only those voxels with an eigenvalue ≥0.4 in one of the three canonical directions. a, Shows the proportion of voxels for the maximum value in each direction. b, Illustrates eigenvalues for all three directions across all voxels with at least one eigenvalue ≥0.4, sorted by maximum value in each row (i.e., each row is one voxel; heat map indicates the eigenvalue at that voxel for each canonical direction). SCR, superior corona radiata; CC, corpus callosum; FO, fronto-occipital; AP, anterior–posterior; LR, left–right; SI, superior–inferior.
Mentions: One white matter cluster included the superior longitudinal fasciculus, superior corona radiata, and body of the corpus callosum (Fig. 1A,C,D), as well as a region along the posterior thalamic radiation (Fig. 1C). White matter voxels were predominantly (68%; Fig. 5) superior–inferior in orientation (Fig. 5). The most spatially similar gray matter cluster included primarily posterior cortical regions (Fig. 1A-D) such as the precuneus (Fig. 1B) and bilateral intraparietal sulcus (Fig. 1C). This cluster also included anterior temporal cortex (Fig. 1A) and smaller bilateral regions of posterior middle frontal gyrus (Fig. 1D). The gray matter cluster was characterized by a steep negative slope in the 8-10.5 year age bin and more positive slopes in other age groups; white matter age slopes followed a similar trend, though slopes were generally positive (indicating increasing volume with age; Fig. 1E-F).

Bottom Line: Linear effects of age on white and gray matter volume were modeled within four age bins, spanning 4-18 years, each including 90 participants (45 male).Four white matter clusters were identified, each with a dominant direction of underlying fibers: anterior-posterior, left-right, and two clusters with superior-inferior directions.Pairs of gray and white matter clusters followed parallel slope trajectories, with white matter changes generally positive from 8 years onward (indicating volume increases) and gray matter negative (decreases).

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Radiology, Cumming School of Medicine, University of Calgary , Calgary, Alberta, Canada T2N 1N4 ; Department of Pediatrics, Cumming School of Medicine, University of Calgary , Calgary, Alberta, Canada T2N 1N4 ; Child and Adolescent Imaging Research Program, Alberta Children's Hospital , Calgary, Alberta, Canada T3B 6A8 ; Alberta Children's Hospital Research Institute , Calgary, Alberta, Canada T3B 6A8.

ABSTRACT
The human brain develops with a nonlinear contraction of gray matter across late childhood and adolescence with a concomitant increase in white matter volume. Across the adult population, properties of cortical gray matter covary within networks that may represent organizational units for development and degeneration. Although gray matter covariance may be strongest within structurally connected networks, the relationship to volume changes in white matter remains poorly characterized. In the present study we examined age-related trends in white and gray matter volume using T1-weighted MR images from 360 human participants from the NIH MRI study of Normal Brain Development. Images were processed through a voxel-based morphometry pipeline. Linear effects of age on white and gray matter volume were modeled within four age bins, spanning 4-18 years, each including 90 participants (45 male). White and gray matter age-slope maps were separately entered into k-means clustering to identify regions with similar age-related variability across the four age bins. Four white matter clusters were identified, each with a dominant direction of underlying fibers: anterior-posterior, left-right, and two clusters with superior-inferior directions. Corresponding, spatially proximal, gray matter clusters encompassed largely cerebellar, fronto-insular, posterior, and sensorimotor regions, respectively. Pairs of gray and white matter clusters followed parallel slope trajectories, with white matter changes generally positive from 8 years onward (indicating volume increases) and gray matter negative (decreases). As developmental disorders likely target networks rather than individual regions, characterizing typical coordination of white and gray matter development can provide a normative benchmark for understanding atypical development.

No MeSH data available.


Related in: MedlinePlus