健康与遗传心理学研究室知识库

本研究以注意控制理论为背景，采用事件相关电位（Event-related potentials, ERP）技术，选取高低特质焦虑个体作为被试，探讨了特质焦虑个体执行功能改变的潜在神经机制。 研究主要探讨特质焦虑个体的反应抑制及工作记忆更新功能的特点。实验一采用ERP及源电流密度分析的方法，结合经典的反应抑制范式Go/Nogo任务，分别考察高低特质焦虑个体Go及Nogo条件下的N2及P3成分。传统研究表明N2反映了反应抑制的早期加工阶段——冲突监控加工，P3则反映了反应抑制的晚期加工阶段——对抑制反应与否的评估。结果发现，高特质焦虑个体相比于低特质焦虑个体主要表现为P3波幅的下降，进而对Go减去Nogo条件的差异波的进行源分析发现，这种改变主要由前额叶特别是前扣带回参与，因此推断特质焦虑个体的反应抑制功能失调主要是由前额叶参与的反应抑制评估功能受限所引发的。实验二，我们进一步采用ERP技术考察特质焦虑和状态焦虑对工作记忆的刷新功能的影响，将被试分为高特质焦虑组和低特质焦虑组，同时采用观看恐怖影片的方式诱导被试的状态焦虑，被试分别完成空间2-back及言语2-back任务，以其验证注意控制理论提出的特质焦虑及状态焦虑可能对不同类型工作记忆的刷新功能产生影响。结果发现，与低特质焦虑个体相比，高特质焦虑个体工作记忆更新功能相关的P300成分表现出波幅的下降，同时高状态焦虑也使得P300成分波幅降低，但是这些改变不受工作记忆的类型的影响。 整个研究我们部分的验证了焦虑相关的注意控制理论，即焦虑对反应抑制及工作记忆更新功能都有影响，但这种影响在反应抑制加工阶段是特异于抑制晚期阶段的，而对于工作记忆更新功能则存在着广泛的影响，无记忆类型特异性。

Abstract Based on attention control theory, we used event-related potentials (ERP) technique to explore the effects of anxiety on executive function with high and low trait anxiety individuals. The current study consisted of two experiments. In the Experiment 1, we used ERP to examine the effect of trait anxiety on response inhibition with Go/Nogo paradigm. We focused on the N2 and P3 components in the difference wave between NoGo condition and Go condition, which probably represent different sub-processes of response inhibition. We found the reduced P3 component in HTA group compared with LTA group. Using the standardised Low Resolution Electromagnetic Tomography method (sLORETA), it is shown that this attenuation in HTA was related to the frontal cortex. Therefore, the decline in response inhibition in anxiety is likely mediated by the decreased activation of frontal area. In the experiment 2, we adopted spatial and verbal 2-back tasks to examine the effects of trait anxiety and state anxiety on updating function of working memory. ERP results showed that updating-related P300 component was affected by both state and triat anxiety. The amplitude of P300 attenuated in HTA group as comparing with LTA group and reduced under stress state. No difference was observed between spatial WM and verbal WM. To sum up, the present results gave some supported evidence for attention control theory. There are significant effects of trait anxiety on late stage of response inhibition and type-free updating function of working memory. Keywords: trait anxiety, response inhibition, updating of working memory, Event-related potentials, Current density analysis