U.S. Army Research Laboratory.
Department of Psychology, University of Virginia.
Psychol Aging. 2018 Aug;33(5):855-870. doi: 10.1037/pag0000274.
One of the central concepts within the literature on cognitive aging is the notion of dedifferentiation-the idea that increasing age is associated with an increase in the interrelatedness of different cognitive abilities. Despite the centrality of this dedifferentiation hypothesis, there is a great deal of evidence that both supports and does not support dedifferentiation. We hypothesized that these inconsistent findings were due to (a) the use of different cognitive abilities (i.e., memory vs. speed of processing) that were correlated; and (b) the differing age groups that were used across studies. By using data from 11 well-validated cognitive test batteries (K = 2,355, range of the mean ages of correlations 18-85+), we found evidence for linear dedifferentiation when a test assessing speed of processing was included in the correlation with test of other cognitive abilities. We speculate that previous findings of nonlinear dedifferentiation are likely a result of undiagnosed or unrecognized pathology in a subsample of participants. (PsycINFO Database Record
认知老化文献中的一个核心概念是去分化的概念，即随着年龄的增长，不同认知能力之间的相关性会增加。尽管去分化假说具有核心地位，但有大量证据既支持也不支持去分化。我们假设这些不一致的发现是由于（a）使用了相关的不同认知能力（即记忆与加工速度）；以及（b）不同研究中使用的不同年龄组。通过使用来自 11 个经过充分验证的认知测试电池的数据（K=2355，相关的平均年龄范围为 18-85+），当在与其他认知能力测试的相关性中包含评估加工速度的测试时，我们发现了线性去分化的证据。我们推测，以前发现的非线性去分化很可能是由于参与者的亚样本中存在未诊断或未被识别的病理。
