Uncovering the interaction of key regions within the prefrontal response inhibition network

停止已经启动的反应对于适应日常行为至关重要。例如，每个运动员都知道刚刚开始的动作是错误的或导致劣势的感觉。一个乒乓球运动员可能会注意到——在实际回发球时——发球偏了。这只是人们为了实现目标而不得不在信息发生变化时隐瞒反应的一种情况，但在日常生活中有很多这样的例子。在实验室中，可以使用停止信号任务（SST）等任务来测量抑制已经启动的反应的能力（Verbruggen et al., 2019; Verbruggen & Logan, 2008）。先前的神经影像学研究已经探索了反应抑制的神经基础，并确定了右侧前额叶皮层中的两个关键区域；背外侧前额叶皮层（DLPFC）和额下回（IFG） （Aron等人，2004,2014；Depue等人，2016；Swann等人，2012；Swann等人，2013；Verbruggen等人，2019）。一般来说，假设DLPFC监测环境中停止的需要，一旦需要出现，DLPFC发出信号给正确的IFG，这反过来将作为行为“刹车”来停止行动（Aron等人，2004,2014）。此外，最近的一项功能磁共振研究显示，右侧PFC在跨域抑制任务中存在共同的神经编码（Depue等人，2016）。更具体地说，他们发现DLPFC在所有任务中都很活跃；与IFG不同，IFG只在需要反应抑制的任务中活跃。这些结果符合前额皮质功能和抑制控制的流行理论（Schall, Palmeri, & Logan, 2017）。然而，神经影像学研究的结果和假设的相互作用尚未得到最终证实。尽管大多数神经影像学研究隐含地假设任务相关活动的增加与受试者的行为之间存在因果关系，但它们无法就给定认知过程中任务相关活动的功能相关性得出强有力的结论。一种弥合这种差距的方法是通过实验操纵该区域的神经状态。调节个体神经状态的一种方法是使用非侵入性脑刺激技术，如经颅磁刺激（TMS）。目前的项目包括三项针对年轻健康成年人的独立研究。两项研究旨在通过在任务执行前和任务执行期间使用经颅磁刺激的组合来揭示DLPFC和IFG的相互作用。上述经颅磁刺激研究之一将使用更自然的任务，提高生态有效性。此外，第三项研究将考察跨模态对停车能力的影响。

Stopping an already initiated response is vital for adaptive everyday behavior. For example, every athlete knows the feeling that a just initiated action is wrong or leads to a disadvantage. A table tennis player might notice – while actually returning a serve – that the serve went out wide. This is only one situation in which people have to withhold a response once a change of information appears in order to achieve a goal but there are many examples in everyday life. In the laboratory, the ability to inhibit already initiated responses can be measured using tasks such as the Stop-Signal Task (SST) (Verbruggen et al., 2019; Verbruggen & Logan, 2008). Previous neuroimaging studies have explored the neural underpinnings of response inhibition and identified two key regions within the right prefrontal cortex; the dorsolateral prefrontal cortex (DLPFC) and the inferior frontal gyrus (IFG) (Aron et al., 2004, 2014; Depue et al., 2016; Swann et al., 2012; Swann et al., 2013; Verbruggen et al., 2019). In general it is assumed that the DLPFC monitors the environment for the need to stop and once that need arises, the DLPFC signals the right IFG, which in turn will act as a behavioral “brake” to stop the action (Aron et al., 2004, 2014). Furthermore, a recent fMRI study revealed a common neural coding in the right PFC in inhibition tasks across domains (Depue et al., 2016). More specifically, they showed that the DLPFC is active in all tasks; unlike the IFG, which was only active in tasks requiring response inhibition. These results fit prevailing theories of prefrontal cortex function and inhibitory control (Schall, Palmeri, & Logan, 2017). However, the results from neuroimaging studies and the hypothetical interactions have not yet been conclusively proven. Although most neuroimaging studies implicitly assume a causal relation between increased task-related activation and the subject’s behavior, they cannot draw strong conclusions on the functional relevance of task-related activity for a given cognitive process. A way to bridge this gap is by experimentally manipulating the neural state of the area. One way to modulate the neural state of an individual is the use of non-invasive brain stimulation techniques such as transcranial magnetic stimulation (TMS). The present project encompasses three separate studies on young, healthy adults. Two studies aim to uncover the interaction of DLPFC and IFG by using a combination of TMS before and during task-performance. One of the aforementioned TMS studies will use a more naturalistic task and enhance ecological validity. Additionally, a third study will examine the cross-modal influences on stopping capabilities.