Department of Ophthalmology & Visual Sciences, McGill Vision Research, McGill University, Montreal, Quebec, Canada.
Present Address: School of Psychology, University of New South Wales, Sydney, New South Wales, Australia.
J Vis. 2021 Mar 1;21(3):20. doi: 10.1167/jov.21.3.20.
By attending to part of a visual scene, we can prioritize processing of the most relevant visual information and so use our limited resources effectively. Previous functional magnetic resonance imaging (fMRI) work has shown that attention can increase overall blood-oxygen-level-dependent (BOLD) signal responsiveness but also enhances the stimulus information in terms of classifier performance. Here, we investigate how these effects vary across the visual field. We compare attention-enhanced fMRI-BOLD amplitude responses and classifier accuracy in fovea and surrounding stimulus regions using a set of four simple stimuli subdivided into a foveal region (1.4° diameter) and a surround region (15° diameter). We found dissociations between the effects of attention on average response and in enhancing stimulus information. In early visual cortex, we found that attention increased the amplitude of responses to both foveal and surround parts of the stimuli and increased classifier performance only for the surround stimulus. Conversely, ventral visual areas showed less change in average response but greater changes in decoding. Unlike for early visual cortex, in the ventral visual cortex attention produced similar changes in decoding for center and surround stimuli.
通过关注视觉场景的一部分，我们可以优先处理最相关的视觉信息，从而有效地利用我们有限的资源。以前的功能磁共振成像（fMRI）研究表明，注意力可以提高整体血氧水平依赖（BOLD）信号的反应性，同时还可以提高分类器性能方面的刺激信息。在这里，我们研究了这些效果在整个视野中的变化。我们使用一组四个简单的刺激物（分为 1.4°直径的中央区域和 15°直径的周边区域）比较了中央凹和周边刺激区域中注意力增强的 fMRI-BOLD 幅度响应和分类器准确性。我们发现注意力对平均反应和增强刺激信息的影响存在差异。在早期视觉皮层中，我们发现注意力增加了对刺激的中央和周边部分的反应幅度，并仅提高了周边刺激的分类器性能。相反，腹侧视觉区域的平均反应变化较小，但解码的变化较大。与早期视觉皮层不同，在腹侧视觉皮层中，注意力对中心和周边刺激的解码产生了相似的变化。
