Biasing the brain's attentional set: I. Cue driven deployments of intersensory selective attention
Biasing the brain's attentional set: I. Cue driven deployments of intersensory selective attention
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DOI：
10.1007/s00221-005-2378-7
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发表时间：
2005-10-01
影响因子：
2
通讯作者：
Saron, CD
中科院分区：
文献类型：
--
作者：
Foxe, JJ;Simpson, GV;Saron, CD
使用人类事件相关电位的高密度图来检查与将注意力转移到两种可能的感觉方式之一相关的大脑活动。选择性注意力的部署基于视觉呈现的符号提示词，在逐次试验的基础上指导受试者注意哪种感觉方式。我们测量了提示指令和随后的复合听觉-视觉命令性刺激之间大约 1 秒时间内的激活时空模式。这使我们能够在对复合视听目标刺激进行实际选择性处理之前，评估涉及部署和维持感觉间选择性注意力的大脑区域的处理流程。额叶和顶叶区域的活动显示，在预期期的早期（类似于 230 毫秒），感觉特异性激活增加，这可能代表了额顶叶注意力部署系统的激活，以自上而下地控制注意力。在“待关注”刺激到来之前的后期，在额中央区域和顶枕区域观察到持续的差异活动，表明特定感觉的偏向注意力状态的维持，这将允许随后的选择性处理。尽管在这个持续后期存在明显的感觉偏差，但也很明显，两个感觉系统在提示目标期间都在准备中。这些晚期感觉特异性偏差效应还伴随着额叶皮层的持续激活，这些激活也显示出常见的和感觉特异性的激活模式，这表明偏差状态的维持包括来自额叶皮层发生器的自上而下的输入，其中一些是感觉特异性区域。这些数据支持在处理提示信息、部署注意力和维持注意力焦点以预测即将发生的注意力相关输入的过程中感觉、顶叶和额叶区域之间的广泛相互作用。
Brain activity associated with directing attention to one of two possible sensory modalities was examined using high-density mapping of human event-related potentials. The deployment of selective attention was based on visually presented symbolic cue-words instructing subjects on a trial-by-trial basis, which sensory modality to attend. We measured the spatio-temporal pattern of activation in the approximately 1 second period between the cue-instruction and a subsequent compound auditory-visual imperative stimulus. This allowed us to assess the flow of processing across brain regions involved in deploying and sustaining inter-sensory selective attention, prior to the actual selective processing of the compound audio-visual target stimulus. Activity over frontal and parietal areas showed sensory specific increases in activation during the early part of the anticipatory period (similar to 230 ms), probably representing the activation of fronto-parietal attentional deployment systems for top-down control of attention. In the later period preceding the arrival of the "to-be-attended" stimulus, sustained differential activity was seen over fronto-central regions and parieto-occipital regions, suggesting the maintenance of sensory-specific biased attentional states that would allow for subsequent selective processing. Although there was clear sensory biasing in this late sustained period, it was also clear that both sensory systems were being prepared during the cue-target period. These late sensory-specific biasing effects were also accompanied by sustained activations over frontal cortices that also showed both common and sensory specific activation patterns, suggesting that maintenance of the biased state includes top-down inputs from generators in frontal cortices, some of which are sensory-specific regions. These data support extensive interactions between sensory, parietal and frontal regions during processing of cue information, deployment of attention, and maintenance of the focus of attention in anticipation of impending attentionally relevant input.