Opposite Neural Signatures of Motion-Induced Blindness in Human Dorsal and Ventral Visual Cortex
Opposite Neural Signatures of Motion-Induced Blindness in Human Dorsal and Ventral Visual Cortex
复制标题
DOI：
10.1523/jneurosci.2371-08.2008
复制
发表时间：
2008-10-08
影响因子：
5.3
通讯作者：
Heeger, David J.
中科院分区：
文献类型：
--
作者：
Donner, Tobias H.;Sagi, Dov;Heeger, David J.
运动引起的失明（MIB）是一种视觉现象，当显着的静态目标被移动的掩模图案包围时，它会自发地在视觉意识中进出。据推测，MIB 反映了静态目标和移动掩模的皮质表征之间的对抗性相互作用。在这里，我们报告了 MIB 期间人类腹侧和背侧视觉皮层之间这种拮抗作用的证据。腹侧视觉区 V4 的功能性磁共振成像 (fMRI) 反应随着目标的主观消失而降低。这些反应降低是与目标视网膜局部相对应的皮层亚区域特有的，相对于知觉报告发生得较早，并且不能用对目标消失反应的注意力转移来解释。与此同时，顶内沟内及其周围的背侧视觉区域中面罩特定亚区域的反应增加。腹侧和背侧视觉区域的这些相反反应仅发生在主观目标消失期间，而不是在目标被物理移除时发生。此外，目标消失的感知报告还与活动的“全局”调节相关，对于主观目标消失和物理目标去除，这种调节在时间上被延迟，并且在整个早期视觉皮层中都很明显。我们得出的结论是，目标的意识与其腹侧视觉皮层中的表征强度紧密相关，而背侧视觉皮层中的掩模表征在 MIB 期间目标表征的自发抑制中起着至关重要的作用。
Motion-induced blindness (MIB) is a visual phenomenon in which a salient static target spontaneously fluctuates in and out of visual awareness when surrounded by a moving mask pattern. It has been hypothesized that MIB reflects an antagonistic interplay between cortical representations of the static target and moving mask. Here, we report evidence for such antagonism between human ventral and dorsal visual cortex during MIB. Functional magnetic resonance imaging ( fMRI) responses in ventral visual area V4 decreased with the subjective disappearance of the target. These response decreases were specific for the cortical subregion corresponding retinotopically to the target, occurred early in time with respect to the perceptual report, and could not be explained by shifts of attention in reaction to target disappearance. At the same time, responses increased in mask-specific subregions in dorsal visual areas in and around the intraparietal sulcus. These opposite responses in ventral and dorsal visual areas occurred only during subjective target disappearance, not when the target was physically removed. Perceptual reports of target disappearance were furthermore associated with a "global" modulation of activity, which was delayed in time, and evident throughout early visual cortex, for both subjective target disappearance and physical target removal. We conclude that awareness of the target is tightly linked to the strength of its representation in ventral visual cortex, and that the mask representation in dorsal visual cortex plays a crucial role in the spontaneous suppression of the target representation during MIB.