Neuroscience Graduate Program, University of California San Diego, La Jolla, California, USA.
Nat Neurosci. 2013 Dec;16(12):1879-87. doi: 10.1038/nn.3574. Epub 2013 Nov 10.
Computational theories propose that attention modulates the topographical landscape of spatial 'priority' maps in regions of the visual cortex so that the location of an important object is associated with higher activation levels. Although studies of single-unit recordings have demonstrated attention-related increases in the gain of neural responses and changes in the size of spatial receptive fields, the net effect of these modulations on the topography of region-level priority maps has not been investigated. Here we used functional magnetic resonance imaging and a multivariate encoding model to reconstruct spatial representations of attended and ignored stimuli using activation patterns across entire visual areas. These reconstructed spatial representations reveal the influence of attention on the amplitude and size of stimulus representations within putative priority maps across the visual hierarchy. Our results suggest that attention increases the amplitude of stimulus representations in these spatial maps, particularly in higher visual areas, but does not substantively change their size.
计算理论提出,注意力调节视觉皮层区域中空间“优先”图的地形景观,使得重要物体的位置与更高的激活水平相关联。尽管对单个单元记录的研究已经证明了与注意力相关的神经反应增益增加和空间感受野大小的变化,但这些调制对区域水平优先图地形的净效应尚未得到研究。在这里,我们使用功能磁共振成像和多元编码模型,使用整个视觉区域的激活模式来重建被注意和忽略刺激的空间表示。这些重建的空间表示揭示了注意力对视觉层次结构中假定的优先图内刺激表示的幅度和大小的影响。我们的结果表明,注意力增加了这些空间图中刺激表示的幅度,特别是在更高的视觉区域,但实质上不改变它们的大小。