Competition for priority in processing increases prefrontal cortex's involvement in top-down control: an event-related fMRI study of the stroop task
Competition for priority in processing increases prefrontal cortex's involvement in top-down control: an event-related fMRI study of the stroop task
复制标题
DOI：
10.1016/s0926-6410(03)00108-3
复制
发表时间：
2003-07-01
期刊：
影响因子：
--
通讯作者：
Barada, V
中科院分区：
文献类型：
--
作者：
Milham, MP;Banich, MT;Barada, V
先前的研究表明，与任务无关的信息的各个方面（例如其显着性、任务相关性、情绪性）可以增加前额叶皮层（PFC）在自上而下的注意力控制中的参与。根据这些发现，我们假设当与任务无关的信息争夺处理优先权时，PFC 的参与会增加。在一项使用 Stroop 任务的奇怪变体的事件相关功能磁共振成像研究中，我们使用三种操作来检查该假设的普遍性，这些操作旨在提高与任务无关的信息竞争处理优先级的能力。首先，我们研究了与任务无关的信息的出现频率如何影响 PFC 活动。其次，我们检查了冲突的颜色信息（即不一致的试验）是否会增加 PFC 区域的活动，这些区域与对不经常出现的任务无关信息敏感的区域相似或不同。最后，我们研究了可能发生冲突的级别数量的影响（例如仅不响应、不响应和响应）。对于不经常出现的任务无关信息，后背外侧和后下 PFC 的活动增加，当任务无关信息包含冲突的颜色信息时活动最大。相比之下，只有当存在冲突的颜色信息时，中背外侧前额叶皮层的活动才会增加，当冲突发生在多个级别时，活动增加最多。前扣带回主要对反应水平上冲突的发生敏感，只有一小部分区域对无反应冲突也表现出敏感性。根据这些发现，我们认为后部 DLPFC 和 PIPFC 参与后处理系统的偏置处理，中 DLPFC 参与偏置工作记忆内容的处理，而 ACC 主要参与反应相关过程。 (C) 2003 Elsevier B.V. 保留所有权利。
Prior work indicates that various aspects of task-irrelevant information (e.g. its salience, task-relatedness, emotionality) can increase the involvement of prefrontal cortex (PFC) in top-down attentional control. In light of these findings, we hypothesize that PFC's involvement increases when task-irrelevant information competes for priority in processing. In an event-related fMRI study using an oddball variant of the Stroop task, we examine the generality of this hypothesis using three manipulations designed to increase the ability of task-irrelevant information to compete for priority in processing. First, we investigated how the frequency of occurrence of task-irrelevant information affects PFC activity. Second, we examined whether conflicting color information (i.e. incongruent trials) increases activity in regions of PFC that are similar to or distinct from those sensitive to infrequently occurring task-irrelevant information. Finally, we examined the impact of the number of levels at which conflict could occur (e.g. non-response only, non-response and response). Activity in posterior-dorsolateral and posterior-inferior PFC increased for infrequently occurring task-irrelevant information, being largest when the task-irrelevant information contained conflicting color-information. In contrast, increases in mid-dorsolateral prefrontal cortex's activity were only noted when conflicting color information was present, being largest when conflict occurred at multiple levels. The anterior cingulate was primarily sensitive to the occurrence of conflict at the response level with only a small sub-region exhibiting sensitivity to non-response conflict as well. From these findings we suggest that posterior DLPFC and PIPFC are involved in biasing processing in posterior processing systems, mid-DLPFC is involved in biasing the processing of the contents of working memory, and ACC is primarily involved in response-related processes. (C) 2003 Elsevier B.V. All rights reserved.