Article Figures & Data
Figures
- Fig. 1.
Gray matter density age effect statistical maps (left, right, andtop views) showing gray matter density changes between childhood and adolescence (A) and between adolescence and adulthood (B). Anatomically, the central sulcus and sylvian fissure are shown inblack. Shades of green toyellow represent negative Pearson's correlation coefficients (gray matter loss with increasing age), and shades ofblue, purple, and pinkrepresent positive Pearson's correlation coefficients (gray matter gain with age) according to the color baron the right (range of Pearson's correlation coefficients from −1.0 to 1.0). Regions shown in redcorrespond to correlation coefficients that have significant negative age effects at a threshold of p = 0.05 (gray matter loss), and regions shown in white correspond to significant positive age effects at a threshold ofp = 0.05 (gray matter density gain).C, Statistical map of the Fisher'sZ transformation of the difference between Pearson's correlation coefficients for the child to adolescent and the adolescent to adult contrasts (see color bar onright representing Z scores from −5.0 to 5.0). Shades of green to yellow represent regions where the age effects are more significant in the adolescent to adult contrast (B) than in the child to adolescent contrast (A). Highlighted inred are the regions where the difference between Pearson's correlation coefficients is statistically significant (p = 0.05). Shades of blue,purple, and pink represent regions where the age effects are more significant in the child to adolescent contrast than the adolescent to adult contrast. Highlighted inwhite are regions where these effects are significant at a threshold of p = 0.05.
- Fig. 2.
DFC age–effect statistical maps (left, right, and topviews) showing changes in DFC between childhood and adolescence (A) and between adolescence and adulthood (B). Anatomically, the central sulcus and sylvian fissure are shown in black. Shades ofgreen to yellow represent positive Pearson's correlation coefficients (increased DFC or brain growth), and shades of blue, purple, andpink represent negative Pearson's correlation coefficients (decreased DFC or shrinkage) according to the color bar on the right (range of Pearson's correlation coefficients from −1.0 to 1.0). Regions shown inred correspond to correlation coefficients that have significant positive age effects at a threshold ofp = 0.05 (brain growth), and regions shown inwhite correspond to significant negative age effects at a threshold of p = 0.05 (brain shrinkage).C, Statistical map of the Fisher's Ztransformation of the difference between Pearson's correlation coefficients for the child to adolescent and the adolescent to adult contrasts (see color bar on rightrepresenting Z scores from −5.0 to 5.0). Shades ofgreen to yellow represent regions where the age effects are more significant in the adolescent to adult contrast (B) than in the child to adolescent contrast (A). Highlighted in redare the regions where the difference between Pearson's correlation coefficients is statistically significant (p= 0.05). Shades of blue, purple, andpink represent regions where the age effects are more significant in the child to adolescent contrast than the adolescent to adult contrast. Highlighted in white are regions where these effects are significant at a threshold ofp = 0.05. Note the sign of the differences between contrasts is opposite to that in the difference map for the gray matter density contrasts because of the inverse relationship between gray matter density (negative effects) and late brain growth (positive effects).
- Fig. 3.
A, Composite statistical map (top view) showing the correspondence in age effects for changes in DFC and changes in gray matter in the child to adolescent contrast. Shown in green is the Pearson's correlation map of all positive correlation coefficients for DFC (also seen in Fig.2), and in blue is the probability map of all regions of significant gray matter loss (surface point significance threshold,p = 0.05, as shown in Fig. 1). Inred are regions of overlap in the gray and DFC statistical maps. B, Similar composite map for the adolescent to adult age effects. Note the highly spatially consistent relationship between brain growth and reduction in gray matter density. The shapes of the regions of greatest age-related change for the two maps (gray matter and DFC) are nearly identical in many frontal regions in the adolescent to adult contrast. Very few regions of gray matter density reduction fall outside regions of increases in DFC. C, D (left, right, andtop views), Difference between Pearson's correlation coefficients for the age effects for gray matter density and the age effects for DFC between childhood and adolescence (C) and between adolescence and adulthood (D). These maps are similar to those of the difference between correlation coefficients for age effects of gray matter and DFC shown in Figures 1 and 2 but instead highlight the correlation between regions of greatest change in the two separate features of brain maturation measured here (DFC and gray matter density). The color bar represents correspondingZ scores ranging from −5.0 to 5.0 for the difference between correlation coefficients for DFC and gray matter. Highlighted in red are regions of significant negative correlations between DFC and gray matter density (p = 0.05), showing that the relationship between regions of greatest gray matter density reduction are statistically the same as the regions with the greatest brain growth, particularly in the adolescent to adulthood years. Highlighted in white are the regions where the difference between correlation coefficients for the gray matter and DFC maps is positive, indicating that the change with age is in the same direction for both variables (i.e., increased DFC change goes with increased gray matter density change).
- Fig. 4.
Statistical map of the correlation between gray matter density and DFC across all subjects studied. Anatomically, the central sulcus and sylvian fissure are highlighted. Shown in shades of blue, purple, andpink are regions where the correlation is positive (i.e., greater gray density associated with greater DFC), and in shades of green to yellow are regions where the correlation between DFC and gray matter density is negative. Highlighted in red are regions where the negative relationship is highly statistically significant (p = 0.000001). Note that none of the positive correlations between DFC and gray matter density was significant, even when p = 0.01 was used as a threshold.
- Fig. 5.
Differences between groups in DFC shown in millimeters in color (according to the color bar) between childhood and adolescence in both nonscaled (A) and scaled (C) image data sets. Differences between adolescents and adults are also shown in nonscaled (B) and scaled (D) images. Anatomically, the central sulcus and sylvian fissure are shown in black. The maps in the scaled image space allow an assessment of the magnitude (in millimeters) of differences in DFC shown as statistical maps in Figure 2. The samecolor bar applies to both nonscaled and scaled images; regions of brain growth between the younger and older age group tested are shown in dark blue, purple, andpink, and regions of shrinkage between the younger and older groups tested are shown in red,yellow, green, and light blue. Note that whether or not brain size correction is made with scaling, dorsal frontal and posterior temporal lobes show evidence for continued growth after adolescence. Other less robust regions of brain growth or shrinkage are “scaled” out when brain size correction is used to control individual differences.
Tables
Positive effects (increase) Negative effects (decrease) Left Right Left Right Clusters Area Clusters Area Clusters Area Clusters Area Child to adolescent gray matter Frontal 3 162 6 228 51 2481 32 3251 Parietal 2 14 0 0 13 666 18 461 Temporo-occipital 3 4 0 0 13 294 30 280 Adolescent to adult gray matter Frontal 2 15 2 4 23 4463 23 2832 Parietal 13 205 2 22 12 359 18 425 Temporo-occipital 0 0 0 0 12 980 13 431 The number of clusters (sets of two or more significant surface points; p ≤ 0.05) and area in square millimeters is presented by hemisphere and by lobe, and positive and negative effects are shown separately.
- Table 2.
DFC differences between childhood and adolescence and between adolescence and adulthood
Positive effects (growth) Negative effects (shrinkage) Left hemisphere Right hemisphere Left hemisphere Right hemisphere x, y, z Area x, y, z Area x, y, z Area x, y, z Area Childhood to adolescent DFC Frontal −27, 29, −21 19 56, 30, 17 4 −5, 41, −27 402 5, 27, −28 306 −47, 45, −7 41 12, 37, 58 4 −32, 15, −21 59 14, 65, −20 4 −49, 31, 26 26 6, −12, 75 148 −2, 66, −1 7 8, 68, −15 14 −44, 38, 30 8 54, 12, −5 6 −12, 72, 8 6 17, 71, −6 23 −42, 33, 38 18 −4, 67, 8 4 30, 65, −11 4 −26, 43, 44 10 −3, 63, 24 4 7, 72, 5 12 −40, 27, 47 25 −1, 51, 44 9 19, 72, 3 12 −8, −5, 74 65 −3, 46, 50 9 30, 65, 5 13 −52, 12, −2 15 −12, 32, 59 14 36, 64, −2 7 −21, 23, 62 24 20, 70, 16 22 −12, 23, 64 6 4, 67, 18 40 −36, 2, 60 19 27, 54, 36 19 12, 47, 50 20 6, 22, 65 11 22, 19, 65 11 42, 1, 59 4 48, −7, 57 23 Total 227 162 563 545 Parietal −8, −38, 76 49 15, −27, 77 3 −40, −51, 59 174 65, −20, 34 6 −7, −45, 73 5 59, −7, 46 4 −28, −69, 57 6 41, −44, 63 15 −12, −51, 72 9 38, −66, 53 14 Total 63 7 180 35 Temporo-occipital −6, −83, 42 6 20, −81, 49 16 −58, −65, 11 4 69, −27, 1 69 −9, −89, 37 3 11, −82, 46 7 −54, −71, 15 13 51, −77, 13 43 −7, −97, 26 15 37, −83, 34 5 19, −96, 26 19 11, −99, 21 46 66, −26, −21 19 59, −58, −16 7 43, −80, −17 5 Total 24 124 17 112 Adolescent to adult DFC Frontal −15, 57, −21 299 9, 67, −15 3 −47, 47, −7 10 30, 56, 30 9 −17, 27, −25 3 34, 58, 23 3 −49, 40, 11 4 29, 32, 52 15 −14, 62, 29 12 12, 47, 50 9 −26, 62, 21 3 56, 29, 14 31 −32, 41, 40 13 33, 43, 41 27 −33, 55, 25 3 58, 20, 23 144 −13, 41, 54 13 46, 38, 31 3 −25, 39, 46 33 53, −4, 51 26 −30, 38, 45 10 32, 35, 49 24 −40, 40, 33 16 60, −5, 39 29 −21, 32, 57 129 19, 35, 57 19 −42, 34, 38 26 64, −4, 18 78 −30, 23, 57 4 25, 19, 64 46 −49, 35, 23 20 57, 8, −1 20 −7, 17, 69 95 4, 19, 66 196 −53, 31, 14 11 −47, 6, 50 7 13, −2, 74 51 −55, 23, 16 34 11, −17, 79 20 −50, 24, 30 5 43, 7, 55 41 −49, 14, 42 58 −57, 15, 16 148 −55, 11, 1 4 −37, −15, 67 3 Total 585 442 378 352 Parietal −39, −52, 59 5 −62, −4, 24 331 17, −37, 77 24 −49, −49, 54 4 −59, −6, 39 14 21, −42, 72 21 −58, −25, 46 91 43, −51, 57 4 −8, −48, 71 9 13, −62, 65 18 −19, −58, 67 12 3, −73, 47 274 −2, −73, 48 14 14, −86, 41 11 −18, −78, 50 9 −30, −78, 47 5 Total 9 0 485 352 Temporo-occipital −54, −69, −13 19 55, −2, −37 19 33, −84, 36 24 −65, −55, 10 84 69, −46, 5 116 12, −91, 32 39 52, −76, 17 199 10, −97, 22 65 Total 103 334 0 128 The central coordinate (x, y, z) and area in square millimeters is shown for each cluster. The total surface area of significant surface points is presented for each lobe.
Child to adolescent DFC Adolescent to adult DFC Left Right Left Right Positive Negative Positive Negative Positive Negative Positive Negative Gray matter increase 0.9790 0.0184 0.8940 0.0003 0.8819 0.0140 0.7414 0.0163 Gray matter decrease 0.1112 0.8056 0.0634 0.4570 0.0114 0.9506 0.0177 0.5419 The p values from permutation tests assessing positive (increased) and negative (decreased) age effects on DFC within regions of significant gray matter density decrease and separate regions of gray matter density increase are shown.
