Domain general mechanisms of perceptual decision making in human cortex.
Domain general mechanisms of perceptual decision making in human cortex.
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DOI：
10.1523/jneurosci.5984-08.2009
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发表时间：
2009-07-08
期刊：
影响因子：
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通讯作者：
Serences JT
中科院分区：
文献类型：
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作者：
Ho TC;Brown S;Serences JT
为了成功地与环境中的物体交互，必须不断获取、解释和使用感官证据来指导适当的运动反应。例如，驾驶时，红灯应激发电机命令来踩下制动踏板。单单元记录研究已经证实，简单的感觉运动转换是由最终指导行为反应的相同神经元介导的。然而，这些感觉运动区域也有可能是在其他地方计算的独立于模态的决策信号的接收者。在这里，我们使用功能磁共振成像和人类观察者来表明，右侧岛叶子区域的激活时间过程与独立于所需的运动反应方式（眼跳与手动）积累感觉证据的作用一致。此外，计算模型和 BOLD 反应模拟的结合表明，该区域并不是简单地通过一般性唤醒或决策过程中注意力的强直维持来招募的。因此，我们的数据提出了一种可能性，即感觉证据的独立于模态的表示可能会在行为反应开始之前指导效应器特定皮层区域的活动。
To successfully interact with objects in the environment, sensory evidence must be continuously acquired, interpreted, and used to guide appropriate motor responses. For example, when driving, a red light should motivate a motor command to depress the brake pedal. Single-unit recording studies have established that simple sensorimotor transformations are mediated by the same neurons that ultimately guide the behavioral response. However, it is also possible that these sensorimotor regions are the recipients of a modality independent decision signal that is computed elsewhere. Here, we used fMRI and human observers to show that the timecourse of activation in a subregion of the right insula is consistent with a role in accumulating sensory evidence independently from the required motor response modality (saccade vs. manual). Furthermore, a combination of computational modeling and simulations of the BOLD response suggests that this region is not simply recruited by general arousal or by the tonic maintenance of attention during the decision process. Our data thus raise the possibility that a modality-independent representation of sensory evidence may guide activity in effector-specific cortical areas prior to the initiation of a behavioral response.