We have used the magnetisation transfer (MT) MRI measure as a primary measure of myelination in both the gray matter (GM) of the 78 cortical automated anatomical labeling (AAL) regions of the brain, and the underlying white matter in each region, in a cohort of healthy adults (aged 19-62 year old). The results revealed a significant quadratic trend in myelination with age, with average global myelination peaking at 42.9 year old in gray matter, and at 41.7 year old in white matter. We also explored the possibility of using the Nuclear Overhauser Enhancement (NOE) effect, which is acquired in a similar method to MT, as an additional measure of myelination. We found that the MT and NOE signals were strongly correlated in the brain and that the NOE effects displayed similar (albeit weaker) parabolic trends with age. We also investigated differences in cortical thickness with age, and confirmed a previous result of a linear decline of 4.5 ± 1.2 μm/y.

中文翻译：

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在 7 T 测量的年龄相关的骨髓结构差异

我们使用磁化转移 (MT) MRI 测量作为大脑 78 个皮质自动解剖标记 (AAL) 区域的灰质 (GM) 和每个区域的潜在白质髓鞘形成的主要测量方法，在一群健康的成年人（19-62 岁）。结果显示，髓鞘形成随年龄呈显着的二次趋势，灰质的平均全球髓鞘形成峰值为 42.9 岁，白质为 41.7 岁。我们还探讨了使用与 MT 类似的方法获得的核 Overhauser 增强 (NOE) 效应作为髓鞘形成的额外测量的可能性。我们发现 MT 和 NOE 信号在大脑中密切相关，并且 NOE 效应随着年龄的增长显示出相似（尽管较弱）的抛物线趋势。