干扰抑制差异的心理及脑机制

People can readily select useful information while ignoring irrelevant information according to different requirements. The ability to inhibit inappropriate or irrelevant responses is a hallmark of executive control (Miyake et al., 2000). Many previous studies of interference inhibition have employed the classical Stroop paradigm. Stroop interference (Stroop, 1935; MacLeod, 1991) refers to the increase in time taken to name the ink color of an incongruent color-word combination (e.g., the word red printed in blue ink) compared to naming the ink color of a color patch. The Stroop test is widely used as a neuropsychological test to measure selective attention, cognitive flexibility, processing speed, and interference inhibition (Doyle, Biederman, Seidman, Weber, & Faraone, 2000; Howieson, Lezak, & Loring, 2004; Lansbergen, Kenemans, & van Engeland, 2007; MacLeod, 1991; Strauss, Sherman, & Spreen, 2006). A phenomenon known as reverse-Stroop interference was examined by Durgin (2003) in an experiment requiring participants to select a color patch corresponding to a color-word combination's semantic meaning. Traditionally, the Stroop and reverse-Stroop effects are considered approximately equivalent indices of conflict. However, increasing evidence suggests that an experimental dissociation between the two effects can also be observed under certain circumstances. For example, Song and Hakoda (2011) compared the performance of a group with attention deficit and hyperactivity disorder (ADHD), and a paired non-ADHD group on a group version of the Stroop/reverse-Stroop test. They found that ADHD participants were better at resisting Stroop interference compared to reverse-Stroop interference. The experimental dissociation between the Stroop effect and the reverse-Stroop effect in behavioral studies suggests that, although the Stroop and reverse-Stroop effects are postulated to elicit equivalent levels of conflict, the two effects may differ in terms of the magnitude of interference. The behavioral evidence of an experimental dissociation between the Stroop and reverse-Stroop effects discussed above suggests that the Stroop and reverse-Stroop effects might have different functional mechanisms. However, while most brain imaging studies only focused on the functional mechanism (e.g., the prefrontal cortex (PFC) or the ACC) involved in the Stroop effect (Carter et al., 2000; Macleod & MacDonald, 2000; Swick & Jovanovic, 2002; Botvinick, Cohen, & Carter, 2004; Badzakova-Trajkov, Barnett, Waldie, Kirk, Waldie, & Kirk, 2009), the question of differences in the functional mechanisms of the Stroop effect and reverse-Stroop effects remains largely unresolved. Thus, in the present study, we employed the methods of psychophysics and neuroimaging(e.g., functional magnetic resonance imaging, f-MRI) to examine the differences in the functional mechanisms underlying the Stroop and reverse-Stroop effects.

干扰抑制指的是能够根据不同需要选择有关信息忽视无关信息的能力。干扰抑制能力对人类适应环境来讲是非常重要的。Stroop干扰是对干扰抑制进行研究的经典范式，而我们对作为与Stroop干扰相关过程的逆Stroop干扰却很少关注。近年来许多研究发现了两种干扰的实验性分离，这预示着两种干扰的机制存在差异。对两种干扰抑制差异的心理及脑机制进行研究，有助于建构更加精确的干扰抑制模型，回答关于人类如何抑制干扰的基本科学问题。当前对干扰抑制问题的研究需要进一步深化。本项目以干扰抑制差异的心理及脑机制为切入点，利用心理物理学和脑功能成像等手段，试图回答：1)不同干扰抑制（Stroop干扰与逆Stroop干扰）差异的心理实质及影响因素；2)采用f-MRI的方法，来进一步探索干扰抑制差异的神经机制。项目的平台已经搭建，项目负责人在干扰抑制方面的研究有很好的工作基础，为本项目的顺利实施提供了保障。

干扰抑制指的是能够根据不同需要选择有关信息忽视无关信息的能力。干扰抑制能力对人类适应环境来讲是非常重要的。Stroop 干扰是对干扰抑制进行研究的经典范式，而我们对作为与 Stroop 干扰相关过程的逆 Stroop 干扰却很少关注。近年来许多研究发现了两种干扰的实验性分离，这预示着两种干扰的机制存在差异。对两种干扰抑制差异的心理及脑机制进行研究，有助于建构更加精确的干扰抑制模型，回答关于人类如何抑制干扰的基本科学问题。当前对干扰抑制问题的研究需要进一步深化。本项目以干扰抑制差异的心理及脑机制为切入点，利用心理物理学和脑功能成像等手段，试图回答：1)不同干扰抑制（Stroop干扰与逆 Stroop 干扰）差异的心理实质及影响因素；2)采用 f-MRI 的方法，来进一步探索干扰抑制差异的神经机制。脑功能的研究结果发现逆Stroop 干扰激活的脑区比较宽泛，包括 bilateral middle frontal gyrus (BA 9 and BA10), medial frontal gyrus (BA 8), and cingulate gyrus (BA6 and BA 32) 等。Stroop 干扰激活的脑区主要是middle frontal gyrus (BA9)。这说明了两种干扰的神经机制存在差异。在临床上看，逆Stroop 任务可能是一个更加适合来评估干扰抑制的认知神经任务。