Aging affects the scalp-to-cortex distance (SCD) and the comprising tissues. This is crucial for noninvasive neuroimaging and brain stimulation modalities as they rely on traversing from the scalp to the cortex or vice versa. The specific relationship between aging and these tissues has not been comprehensively investigated. We conducted a study on 250 younger and older adults to examine age-related differences in SCD and its constituent tissues. We identified region-specific differences in tissue thicknesses related to age and sex. Older adults exhibit larger SCD in the frontocentral regions compared to younger adults. Men exhibit greater SCD in the inferior scalp regions, while women show similar-to-greater SCD values in regions closer to the vertex compared to men. Younger adults and men have thicker soft tissue layers, whereas women and older adults exhibit thicker compact bone layers. CSF is considerably thicker in older adults, particularly in men. These findings emphasize the need to consider age, sex, and regional differences when interpreting SCD and its implications for noninvasive neuroimaging and brain stimulation.

中文翻译：

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不同年龄组、性别和大脑区域的头皮到皮质组织的差异：对神经影像和大脑刺激技术的影响

衰老会影响头皮到皮质的距离（SCD）及其组成的组织。这对于无创神经成像和大脑刺激方式至关重要，因为它们依赖于从头皮到皮质的遍历，反之亦然。衰老与这些组织之间的具体关系尚未得到全面研究。我们对 250 名年轻人和老年人进行了一项研究，以检查 SCD 及其组成组织与年龄相关的差异。我们确定了与年龄和性别相关的组织厚度的区域特异性差异。与年轻人相比，老年人的额中央区域表现出更大的 SCD。与男性相比，男性在下头皮区域表现出更大的 SCD 值，而女性在靠近头顶的区域表现出类似或更大的 SCD 值。年轻人和男性的软组织层较厚，而女性和老年人的致密骨层较厚。老年人，尤其是男性，脑脊液要厚得多。这些发现强调在解释 SCD 及其对无创神经影像和脑刺激的影响时需要考虑年龄、性别和地区差异。