Barceló Francisco
Department of Psychology, University of the Balearic Islands, Ctra. Valldemossa km 7.5, 07071 Palma de Mallorca, Spain.
Brain Res Brain Res Protoc. 2003 Mar;11(1):27-37. doi: 10.1016/s1385-299x(03)00013-8.
Event-related potentials (ERPs) provide valuable information about the fast brain dynamics subserving cognitive functions such as attention and working memory. Most ERP studies employ cognitive paradigms with a fixed task-set (i.e., press a button to coloured targets), but few have measured ERPs time-locked to shifts in set using a task-switching paradigm. The Madrid card sorting test (MCST) is a dual task protocol in which feedback cues signal unpredictable shifts in set (i.e., from 'sort cards by colour' to 'sort cards by shape'). This protocol allows for an integrated analysis of ERPs to both feedback cues and target card events, providing separate ERP features for the shifting, updating, and rehearsal of attention sets in working memory. Two of these ERP indices are the frontal and posterior aspects of the P300 response. Feedback cues that direct a shift in set also elicit a frontally distributed P3a potential (300-400 ms). Instead, target card events evoke increasingly larger posterior P3b (350-600 ms) activity as the new task set becomes gradually rehearsed. The observed modulations in the frontal and posterior aspects of the P300 response system are interpreted from current models of prefrontal cortex function in the executive control of attention.
事件相关电位（ERPs）为快速大脑动力学提供了有价值的信息，这种动力学支持诸如注意力和工作记忆等认知功能。大多数ERP研究采用具有固定任务集的认知范式（即，对彩色目标按按钮），但很少有研究使用任务切换范式测量与任务集转换时间锁定的ERPs。马德里卡片分类测试（MCST）是一种双重任务协议，其中反馈线索表明任务集的不可预测转换（即，从“按颜色分类卡片”到“按形状分类卡片”）。该协议允许对反馈线索和目标卡片事件的ERPs进行综合分析，为工作记忆中注意力集的转换、更新和复述提供单独的ERP特征。这些ERP指标中的两个是P300反应的额叶和后部方面。指示任务集转换的反馈线索也会引发额叶分布的P3a电位（300 - 400毫秒）。相反，随着新任务集逐渐得到复述，目标卡片事件会引发越来越大的后部P3b（350 - 600毫秒）活动。从当前前额叶皮层功能在注意力执行控制中的模型来解释P300反应系统额叶和后部方面观察到的调制。
