A cortical network sensitive to stimulus salience in a neutral behavioral context across multiple sensory modalities
A cortical network sensitive to stimulus salience in a neutral behavioral context across multiple sensory modalities
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DOI：
10.1152/jn.00636.2001
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发表时间：
2002-01-01
影响因子：
2.5
通讯作者：
Davis, KD
中科院分区：
文献类型：
--
作者：
Downar, J;Crawley, AP;Davis, KD
刺激显著性既取决于行为情境，也取决于其他因素，如新颖性和出现频率。颞顶联合区（TPJ）对行为相关刺激有优先反应，并且被认为在检测显著刺激方面起着一般性作用。如果是这样，即使在中性行为情境下，它也应该对新颖或不常见的事件有优先反应。为了检验这一假设，我们使用事件相关功能磁共振成像（fMRI）来识别在被动观察期间对视觉、听觉和触觉刺激的新颖性敏感的大脑区域。在颞顶联合区的两个部位——缘上回（SMG）和颞上回，确定了在所有模态中对新颖刺激比对熟悉刺激反应更强的皮质区域。右侧额下回（IFG）、右侧前脑岛、左侧前扣带皮层（ACC）和左侧颞下回也显示出对新颖性的敏感性。缘上回中对新颖性敏感的颞顶联合区激活与先前确定的对行为情境敏感的区域重叠。该区域可能在识别显著刺激方面起着一般性作用，无论显著性是否是由于当前行为情境所致。额下回激活与先前确定的无论行为情境如何对非新颖感觉事件有反应的区域重叠。因此，额下回可能在刺激评估中起着一般性作用，而不是在识别新颖刺激方面的特定作用。前扣带皮层激活位于在复杂反应选择任务期间活跃的区域，这表明它在检测和/或规划对显著事件的反应方面起着一般性作用。一个额 - 顶 - 扣带网络可能一般用于识别和评估显著的感觉刺激。
Stimulus salience depends both on behavioral context and on other factors such as novelty and frequency of occurrence. The temporo-parietal junction (TPJ) responds preferentially to behaviorally relevant stimuli and is thought to play a general role in detecting salient stimuli. If so, it should respond preferentially to novel or infrequent events, even in a neutral behavioral context. To test this hypothesis, we used event-related functional magnetic resonance imaging (fMRI) to identify brain regions sensitive to the novelty of visual, auditory, and tactile stimuli during passive observation. Cortical regions with a greater response to novel than familiar stimuli across all modalities were identified at two sites in the TPJ region: the supramarginal gyrus (SMG) and superior temporal gyrus. The right inferior frontal gyrus (IFG), right anterior insula, left anterior cingulate cortex (ACC), and left inferior temporal gyrus also showed sensitivity to novelty. The novelty-sensitive TPJ activation in SMG overlaps a region previously identified as sensitive behavioral context. This region may play a general role in identifying salient stimuli, whether the salience is due to the current behavioral context or not. The IFG activation overlaps regions previously identified as responsive to nonnovel sensory events regardless of behavioral context. The IFG may therefore play a general role in stimulus evaluation rather than a specific role in identifying novel stimuli. The ACC activation lies in a region active during complex response-selection tasks, suggesting a general role in detecting and/or planning responses to salient events. A frontal-parietal-cingulate network may serve to identify and evaluate salient sensory stimuli in general.