Perceptual Expectation Evokes Category-Selective Cortical Activity
Perceptual Expectation Evokes Category-Selective Cortical Activity
复制标题
DOI：
10.1093/cercor/bhp188
复制
发表时间：
2010-05-01
期刊：
影响因子：
3.7
通讯作者：
Yantis, Steven
中科院分区：
文献类型：
--
作者：
Esterman, Michael;Yantis, Steven
定向到一个位置的选择性视觉注意（即使在没有刺激的情况下）增加了视觉皮层相应区域的活动，提高了对目标感知的速度和准确性。我们通过操纵观察者对即将到来的目标类别的期望进一步探索了自上而下对知觉表征的影响。观察者看到一个物体（一张脸或一所房子）逐渐从相位混乱的噪声状态中出现；线索建立了对对象类别的期望。当部分被打乱的物体的类别符合他们的预期时，观察者对面孔（性别歧视）或房屋（结构歧视）的分类速度更快。功能性磁共振成像显示，这种期望与类别特异性视觉皮层活动的预期增加有关，即使在没有对象或类别特异性视觉信息的情况下也是如此。期待一张脸引起梭状回和颞上沟的面部选择皮质区域的活动增加。相反，期待房子会增加海马体旁回的活动。这些结果表明，视觉预期通过预先招募与知觉相关的皮层机制来促进随后的知觉。
Selective visual attention directed to a location (even in the absence of a stimulus) increases activity in the corresponding regions of visual cortex and enhances the speed and accuracy of target perception. We further explored top-down influences on perceptual representations by manipulating observers' expectations about the category of an upcoming target. Observers viewed a display in which an object (either a face or a house) gradually emerged from a state of phase-scrambled noise; a cue established expectation about the object category. Observers were faster to categorize faces (gender discrimination) or houses (structural discrimination) when the category of the partially scrambled object matched their expectation. Functional magnetic resonance imaging revealed that this expectation was associated with anticipatory increases in category-specific visual cortical activity, even in the absence of object- or category-specific visual information. Expecting a face evoked increased activity in face-selective cortical regions in the fusiform gyrus and superior temporal sulcus. Conversely, expecting a house increased activity in parahippocampal gyrus. These results suggest that visual anticipation facilitates subsequent perception by recruiting, in advance, the same cortical mechanisms as those involved in perception.