Talanow Tobias, Kasparbauer Anna-Maria, Steffens Maria, Meyhöfer Inga, Weber Bernd, Smyrnis Nikolaos, Ettinger Ulrich
Department of Psychology, University of Bonn, Bonn, Germany.
Department of Epileptology, University Hospital Bonn, Bonn, Germany; Centre for Economics and Neuroscience, University of Bonn, Nachtigallenweg 86, D-53127 Bonn, Germany.
Brain Cogn. 2016 Aug;107:37-47. doi: 10.1016/j.bandc.2016.05.006. Epub 2016 Jun 28.
The antisaccade task is a prominent tool to investigate the response inhibition component of cognitive control. Recent theoretical accounts explain performance in terms of parallel programming of exogenous and endogenous saccades, linked to the horse race metaphor. Previous studies have tested the hypothesis of competing saccade signals at the behavioral level by selectively slowing the programming of endogenous or exogenous processes e.g. by manipulating the probability of antisaccades in an experimental block. To gain a better understanding of inhibitory control processes in parallel saccade programming, we analyzed task-related eye movements and blood oxygenation level dependent (BOLD) responses obtained using functional magnetic resonance imaging (fMRI) at 3T from 16 healthy participants in a mixed antisaccade and prosaccade task. The frequency of antisaccade trials was manipulated across blocks of high (75%) and low (25%) antisaccade frequency. In blocks with high antisaccade frequency, antisaccade latencies were shorter and error rates lower whilst prosaccade latencies were longer and error rates were higher. At the level of BOLD, activations in the task-related saccade network (left inferior parietal lobe, right inferior parietal sulcus, left precentral gyrus reaching into left middle frontal gyrus and inferior frontal junction) and deactivations in components of the default mode network (bilateral temporal cortex, ventromedial prefrontal cortex) compensated increased cognitive control demands. These findings illustrate context dependent mechanisms underlying the coordination of competing decision signals in volitional gaze control.
反扫视任务是研究认知控制中反应抑制成分的重要工具。最近的理论解释从外源性和内源性扫视的并行编程角度阐述了任务表现，这与赛马隐喻相关。以往的研究通过选择性地减缓内源性或外源性过程的编程，例如在实验块中操纵反扫视的概率，在行为层面测试了竞争性扫视信号的假设。为了更好地理解并行扫视编程中的抑制控制过程，我们分析了16名健康参与者在混合反扫视和顺扫视任务中使用3T功能磁共振成像（fMRI）获得的与任务相关的眼动和血氧水平依赖（BOLD）反应。在高（75%）和低（25%）反扫视频率的块中操纵反扫视试验的频率。在高反扫视频率的块中，反扫视潜伏期较短且错误率较低，而顺扫视潜伏期较长且错误率较高。在BOLD水平上，与任务相关的扫视网络（左侧顶下小叶、右侧顶下沟、延伸至左侧额中回和额下交界的左侧中央前回）的激活以及默认模式网络成分（双侧颞叶皮质、腹内侧前额叶皮质）的失活补偿了增加的认知控制需求。这些发现说明了意志性注视控制中竞争性决策信号协调的上下文依赖机制。
