Mudar Raksha A, Chiang Hsueh-Sheng, Eroh Justin, Nguyen Lydia T, Maguire Mandy J, Spence Jeffrey S, Kung Fanting, Kraut Michael A, Hart John
Department of Speech and Hearing Science, University of Illinois at Urbana-Champaign, Champaign, IL, USA.
Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, USA.
J Alzheimers Dis. 2016;50(2):577-90. doi: 10.3233/JAD-150586.
We examined the effects of amnestic mild cognitive impairment (aMCI) on behavioral (response times and error rates) and scalp-recorded event-related potential (ERP) measures of response execution and inhibition, using Go/NoGo tasks involving basic and superordinate semantic categorization. Twenty-five aMCI (16 F; 68.5±8 years) and 25 age- and gender-matched normal control subjects (16 F; 65.4±7.1 years) completed two visual Go/NoGo tasks. In the single car task, responses were made based on single exemplars of a car (Go) and a dog (NoGo) (basic). In the object animal task, responses were based on multiple exemplars of objects (Go) and animals (NoGo) (superordinate). The aMCI subjects had higher commission errors on the NoGo trials compared to the control subjects, whereas both groups had comparable omission errors and reaction times during the Go trials. The aMCI subjects had significantly prolonged N2 ERP latency during Go and NoGo trials across tasks compared to the controls. Both groups showed similar categorization effects and response type effects in N2/P3 ERP latencies and P3 amplitude. Our findings indicate that altered early neural processing indexed by N2 latency distinguishes subjects with aMCI from controls during the Go/NoGo task. Prolonged Go-N2 latency in aMCI appears to precede behavioral changes in response execution, whereas prolonged NoGo-N2 latency underlies behavioral deterioration in response inhibition.
我们使用涉及基本和上级语义分类的Go/NoGo任务，研究了遗忘型轻度认知障碍（aMCI）对行为（反应时间和错误率）以及头皮记录的反应执行和抑制的事件相关电位（ERP）测量的影响。25名aMCI患者（16名女性；68.5±8岁）和25名年龄及性别匹配的正常对照受试者（16名女性；65.4±7.1岁）完成了两项视觉Go/NoGo任务。在单辆车任务中，根据汽车（Go）和狗（NoGo）的单个示例（基本）做出反应。在物体动物任务中，反应基于物体（Go）和动物（NoGo）的多个示例（上级）。与对照受试者相比，aMCI受试者在NoGo试验中的误判错误更高，而两组在Go试验中的漏判错误和反应时间相当。与对照组相比，aMCI受试者在跨任务的Go和NoGo试验中N2 ERP潜伏期显著延长。两组在N2/P3 ERP潜伏期和P3波幅上均表现出相似的分类效应和反应类型效应。我们的研究结果表明，在Go/NoGo任务中，由N2潜伏期索引的早期神经处理改变可将aMCI受试者与对照组区分开来。aMCI中Go-N2潜伏期延长似乎先于反应执行中的行为变化，而NoGo-N2潜伏期延长是反应抑制中行为恶化的基础。
