Irwin Lauren N, Kofler Michael J, Soto Elia F, Groves Nicole B
Department of Psychology, Florida State University.
Neuropsychology. 2019 May;33(4):470-481. doi: 10.1037/neu0000546. Epub 2019 Apr 4.
Set shifting, or cognitive flexibility, is a core executive function involving the ability to quickly and efficiently shift back and forth between mental sets. Meta-analysis suggests medium-magnitude shifting impairments in attention-deficit/hyperactivity disorder (ADHD). However, this conclusion may be premature because the evidence-base relies exclusively on tasks that have been criticized for poor construct validity and may better reflect general neuropsychological functioning rather than shifting specifically.
A well-characterized sample of 77 children ages 8-13 (M = 10.46, SD = 1.54; 32 girls; 66% Caucasian/non-Hispanic) with ADHD (n = 43) and without ADHD (n = 34) completed the criterion global-local set shifting task and 2 counterbalanced control tasks that were identical in all aspects except the key processes.
The experimental manipulation was successful at evoking set shifting demands during the global-local versus both nonshift control tasks (p < .001; ω2 = .12-.14). Mixed-model analyses of variance (ANOVAs) revealed that the ADHD group did not demonstrate disproportional decrements in speed shift costs on the shifting versus nonshift control tasks (p = .30; ω2 = .002), suggesting no evidence of impaired set shifting abilities in ADHD. In contrast, the ADHD group made disproportionately more shifting errors than the non-ADHD group (p = .03; ω2 = 0.03) that were more parsimoniously attributable to prerequisite (nonshifting) processes necessary for successful performance on the global-local task.
Children with ADHD's impaired performance on shifting tasks may be attributable to difficulties maintaining competing rule sets and/or inhibiting currently active rule sets prior to shifting. However, when these higher-order processes are executed successfully, there is no significant evidence to suggest a unique set shifting deficit in ADHD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
任务转换，即认知灵活性，是一项核心执行功能，涉及在思维定式之间快速、高效地来回转换的能力。元分析表明，注意力缺陷多动障碍（ADHD）患者存在中等程度的转换障碍。然而，这一结论可能为时过早，因为证据基础完全依赖于一些任务，这些任务因结构效度差而受到批评，可能更能反映一般神经心理功能，而非特定的转换功能。
选取77名8至13岁（M = 10.46，SD = 1.54；32名女孩；66%为白种人/非西班牙裔）的儿童作为特征明确的样本，其中43名患有ADHD，34名未患ADHD，他们完成了标准的全局-局部任务转换任务以及2项平衡控制任务，这2项控制任务在所有方面均相同，只是关键过程有所不同。
实验操作成功地在全局-局部任务与两个非转换控制任务中引发了任务转换需求（p <.001；ω2 =.12 -.14）。混合模型方差分析（ANOVA）显示，ADHD组在转换任务与非转换控制任务上的速度转换成本并未出现不成比例的下降（p =.30；ω2 =.002），这表明没有证据表明ADHD患者的任务转换能力受损。相比之下，ADHD组比非ADHD组出现了更多不成比例的转换错误（p =.03；ω2 = 0.03），这些错误更可能归因于在全局-局部任务上成功执行所需的前提（非转换）过程。
患有ADHD的儿童在转换任务上表现受损，可能是由于在转换之前难以维持相互竞争的规则集和/或抑制当前活跃的规则集。然而，当这些高阶过程成功执行时，没有显著证据表明ADHD存在独特的任务转换缺陷。（PsycINFO数据库记录（c）2019美国心理学会，保留所有权利）
