Spatial Attention Improves the Quality of Population Codes in Human Visual Cortex
Spatial Attention Improves the Quality of Population Codes in Human Visual Cortex
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DOI：
10.1152/jn.00369.2010
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发表时间：
2010-08-01
影响因子：
2.5
通讯作者：
Serences, John T.
中科院分区：
文献类型：
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作者：
Saproo, Sameer;Serences, John T.
萨普罗·S，塞伦斯·JT。空间注意力提高了人类视觉皮层群体编码的质量。 J Neurophysiol 104: 885-895, 2010。首次发表于 2010 年 5 月 19 日； doi：10.1152/jn.00369.2010。选择性注意能够更详细地处理来自行为相关刺激的感官输入，从而使这些刺激能够更准确地影响思想、行动和未来目标。注意力已被证明可以调节编码基本刺激属性（颜色、方向等）的单一特征选择性神经元的尖峰活动。然而，需要来自许多此类神经元的组合输出来形成相关对象的稳定表示，并且很少有实证工作正式研究了群体反应的注意力调节与编码精度提高之间的关系。在这里，我们使用功能性 MRI 和基于体素的特征调整函数来表明，空间注意力会导致早期视觉皮层中方向选择性群体反应曲线的乘法缩放。反过来，这种乘法缩放与编码精度的提高相关，正如群体反应和关注刺激方向之间的互信息的同时增加所证明的那样。因此，这些数据证明了神经反应的乘法缩放如何提供至少一种机制，通过该机制空间注意力可以提高群体代码的编码精度。早期视觉区域编码精度的提高可能会提高由高阶神经机制计算的感知决策的速度和准确性。
Saproo S, Serences JT. Spatial attention improves the quality of population codes in human visual cortex. J Neurophysiol 104: 885-895, 2010. First published May 19, 2010; doi: 10.1152/jn.00369.2010. Selective attention enables sensory input from behaviorally relevant stimuli to be processed in greater detail, so that these stimuli can more accurately influence thoughts, actions, and future goals. Attention has been shown to modulate the spiking activity of single feature-selective neurons that encode basic stimulus properties (color, orientation, etc.). However, the combined output from many such neurons is required to form stable representations of relevant objects and little empirical work has formally investigated the relationship between attentional modulations on population responses and improvements in encoding precision. Here, we used functional MRI and voxel-based feature tuning functions to show that spatial attention induces a multiplicative scaling in orientation-selective population response profiles in early visual cortex. In turn, this multiplicative scaling correlates with an improvement in encoding precision, as evidenced by a concurrent increase in the mutual information between population responses and the orientation of attended stimuli. These data therefore demonstrate how multiplicative scaling of neural responses provides at least one mechanism by which spatial attention may improve the encoding precision of population codes. Increased encoding precision in early visual areas may then enhance the speed and accuracy of perceptual decisions computed by higher-order neural mechanisms.