Fong Manson Cheuk-Man, Hui Nga Yan, Fung Edith Sze Wan, Chu Patrick Chun Kau, Wang William Shi-Yuan
Department of Chinese and Bilingual Studies, The Hong Kong Polytechnic University, Hong Kong.
Department of Chinese and Bilingual Studies, The Hong Kong Polytechnic University, Hong Kong.
Neurosci Lett. 2018 Mar 23;670:31-35. doi: 10.1016/j.neulet.2018.01.037. Epub 2018 Jan 31.
The N2 component is a well-known neural correlate of conflict monitoring (CM), being more negative in the presence of conflicting information in visual conflict tasks. However, whether to-be-ignored auditory distractors can introduce additional conflict remains unknown. In the present work, subjects performed a visual (V) and audiovisual (AV) version of a Go/NoGo flanker task, and responded only if the target arrow pointed toward a pre-specified direction (e.g., left). In the AV task, in which to-be-ignored auditory distractors that were semantically associated with the flankers were concurrently presented, the congruency effect on both RT and N2 amplitude was enhanced, confirming that additional conflict can be brought about by cross-modal distractors at both behavioural and neural levels. Consistent with the hypothesis that N2 amplitude reflects response conflict in visual conflict tasks, within-subject correlation between N2 amplitude and RT was significant in the Go conditions for the V task (congruent/incongruent). However, for the AV task, the correlation was significant only in the congruent condition. These findings suggest that while the cross-modal conflict is registered by the CM process, only part of this conflict could effectively induce response conflict.
N2成分是冲突监测（CM）中一个广为人知的神经关联指标，在视觉冲突任务中，当出现冲突信息时其负性更强。然而，待忽略的听觉干扰物是否会引入额外的冲突尚不清楚。在本研究中，受试者执行了视觉（V）和视听（AV）版本的Go/NoGo侧翼任务，并且仅在目标箭头指向预先指定的方向（例如，向左）时做出反应。在AV任务中，与侧翼刺激语义相关的待忽略听觉干扰物同时呈现，结果对反应时（RT）和N2波幅的一致性效应均增强，这证实了跨模态干扰物在行为和神经水平上均可引发额外的冲突。与N2波幅反映视觉冲突任务中的反应冲突这一假设一致，在V任务的Go条件下（一致/不一致），N2波幅与RT之间的受试者内相关性显著。然而，对于AV任务，该相关性仅在一致条件下显著。这些发现表明，虽然跨模态冲突由CM过程记录，但只有部分冲突能够有效诱发反应冲突。
