Recent work suggests that indentations of the cerebral cortex, or sulci, may be uniquely vulnerable to atrophy in aging and Alzheimer's disease (AD) and that the posteromedial cortex (PMC) is particularly vulnerable to atrophy and pathology accumulation. However, these studies did not consider small, shallow, and variable tertiary sulci that are located in association cortices and are often associated with human-specific aspects of cognition. Here, we manually defined 4,362 PMC sulci in 432 hemispheres in 216 human participants (50.5% female) and found that these smaller putative tertiary sulci showed more age- and AD-related thinning than larger, more consistent sulci, with the strongest effects for two newly uncovered sulci. A model-based approach relating sulcal morphology to cognition identified that a subset of these sulci was most associated with memory and executive function scores in older adults. These findings lend support to the retrogenesis hypothesis linking brain development and aging and provide new neuroanatomical targets for future studies of aging and AD.

最近的研究表明，大脑皮层的凹陷或脑沟可能在衰老和阿尔茨海默病（AD）中特别容易出现萎缩，而后内侧皮质（PMC）特别容易出现萎缩和病理积累。然而，这些研究没有考虑位于联合皮层且通常与人类特定的认知方面相关的小、浅且可变的第三沟。在这里，我们手动定义了 216 名人类参与者（50.5% 女性）432 个半球的 4,362 个 PMC 脑沟，发现这些较小的假定第三脑沟比较大、更一致的脑沟显示出更多与年龄和 AD 相关的变薄，其中对两个脑沟的影响最强新发现的脑沟。一种将脑沟形态与认知联系起来的基于模型的方法发现，这些脑沟的一个子集与老年人的记忆和执行功能得分最相关。这些发现支持了将大脑发育和衰老联系起来的逆发生假说，并为未来的衰老和 AD 研究提供了新的神经解剖学目标。