Identifying a preclinical phase of Alzheimer’s Disease (PCAD) that is distinct from cognitive changes in healthy aging continues to be a major research focus. Combining neuropsychological and neuroimaging methodologies should improve our ability to differentiate healthy from pathological aging, although studies that utilize both methods often result in equivocal findings, possibly due to variability in cognitive test performance that may be capturing distinct phenotypes. One method of capturing this cognitive variability is to utilize contrasting neuropsychological tests to identify subgroups representative of distinct cognitive phenotypes, and determine whether differences in brain morphometry support these classifications. We review several approaches to defining cognitive subgroups, and we consider the possibility that cognitive asymmetry might provide one means of identifying both functional and structural changes associated with aging and dementia.

中文翻译：

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认知表型、脑形态测量和临床前 AD 中认知下降的检测。

识别不同于健康老龄化认知变化的阿尔茨海默病 (PCAD) 的临床前阶段仍然是一个主要的研究重点。结合神经心理学和神经影像学方法应该可以提高我们区分健康与病理性衰老的能力，尽管使用这两种方法的研究通常会导致模棱两可的结果，这可能是由于认知测试表现的可变性可能会捕捉到不同的表型。捕捉这种认知变异的一种方法是利用对比神经心理学测试来识别代表不同认知表型的亚组，并确定大脑形态测量学的差异是否支持这些分类。我们回顾了定义认知亚组的几种方法，