Department of Psychology, Queen's University.
Department of Psychiatry and Behavioural Neuroscience, McMaster University.
Neuropsychology. 2021 Jan;35(1):33-41. doi: 10.1037/neu0000717.
Traditional neuropsychological assessment methods identify a subpopulation of individuals with Major Depressive Disorder (MDD) who demonstrate cognitive functioning below population norms. An even larger proportion of those with MDD self-report problems with cognition that interfere with daily roles and responsibilities. We aim to test whether an intraindividual deviation of cognitive functioning relative to premorbid estimates (idiographic impairment) may better characterize challenges for functional recovery in MDD.
Adult participants with MDD (N = 111) who completed a baseline neuropsychological assessment battery for a cognitive remediation trial were used in analyses. We compared the frequency of cognitive impairment using the normative and idiographic approaches and examined how these indexes related to observed functioning, perceived functioning, and depression severity.
While only 25% of the sample would be classified as cognitively impaired on a composite measure according to normative comparison standards, 62.2% of this group were classified as idiographically impaired using a conservative cut-off of at least 1 SD deviation below premorbid estimates. Idiographic cognitive impairment shared a stronger inverse relationship with perceived functional competence than normative cognitive impairment. Depressive symptoms did not significantly correlate with both normative and idiographic impairment.
In MDD, reliance on assessment of contemporary cognitive functioning might underestimate rates of those who could be considered cognitively impaired. Consideration of idiographic impairment may help explain gaps between normatively defined cognitive ability with subjective complaints and disability in MDD. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
传统的神经心理学评估方法识别出有抑郁障碍（MDD）的个体，他们的认知功能低于人群水平。甚至有更大比例的 MDD 患者自我报告认知问题，这些问题会干扰他们的日常角色和责任。我们旨在测试认知功能相对于发病前估计的个体内偏差（个体内损伤）是否可以更好地描述 MDD 中功能恢复的挑战。
在认知矫正试验中完成基线神经心理学评估的 MDD 成年参与者（N=111）用于分析。我们比较了使用规范和个体内方法的认知障碍的频率，并研究了这些指标与观察到的功能、感知功能和抑郁严重程度的关系。
虽然只有 25%的样本根据规范比较标准在综合测量上被归类为认知受损，但在使用至少 1 个标准差低于发病前估计的保守截止值的情况下，该组中有 62.2%被归类为个体内损伤。个体内认知损伤与感知功能能力的负相关性比规范认知损伤更强。抑郁症状与规范和个体内损伤均无显著相关性。
在 MDD 中，依赖于对当代认知功能的评估可能会低估被认为认知受损的人数。考虑个体内损伤可能有助于解释 MDD 中规范定义的认知能力与主观抱怨和残疾之间的差距。
