Mangun G R, Hinrichs H, Scholz M, Mueller-Gaertner H W, Herzog H, Krause B J, Tellman L, Kemna L, Heinze H J
Center for Cognitive Neuroscience, Duke University, Box 90999, Durham, NC 27708, USA.
Vision Res. 2001;41(10-11):1423-35. doi: 10.1016/s0042-6989(01)00046-3.
Visual-spatial attention involves modulations of activity in human visual cortex as indexed by electrophysiological and functional neuroimaging measures. Prior studies investigating the time course and functional anatomy of spatial attention mechanisms in visual cortex have used higher-order discrimination tasks with complex stimuli (e.g. symbol matching in bilateral stimulus arrays, or letter discrimination), or simple detection tasks but in the presence of complex distracting information (e.g. luminance detection with superimposed symbols as distractors). Here we tested the hypothesis that short-latency modulations of incoming sensory signals in extrastriate visual cortex reflect an early spatially specific attentional mechanism. We sought evidence of attentional modulations of sensory input processing for simple, isolated stimuli requiring only an elementary discrimination (i.e. size discrimination). As in prior studies using complex symbols, we observed attention-related changes in regional cerebral blood flow in extrastriate visual cortex that were associated with changes in event-related potentials at a specific latency range. These findings support the idea that early in cortical processing, spatially-specific attentional selection mechanisms can modulate incoming sensory signals based on their spatial location and perhaps independently of higher-order stimulus form.
视觉空间注意力涉及人类视觉皮层活动的调节，这可通过电生理和功能性神经成像测量来索引。先前研究视觉皮层中空间注意力机制的时间进程和功能解剖学，使用的是具有复杂刺激的高阶辨别任务（例如双侧刺激阵列中的符号匹配或字母辨别），或者是简单检测任务，但存在复杂的干扰信息（例如以叠加符号作为干扰物的亮度检测）。在这里，我们测试了一个假设，即纹外视觉皮层中传入感觉信号的短潜伏期调节反映了一种早期的空间特异性注意力机制。我们寻找了仅需要基本辨别（即大小辨别）的简单、孤立刺激的感觉输入处理的注意力调节证据。与先前使用复杂符号的研究一样，我们观察到纹外视觉皮层中与注意力相关区域脑血流的变化，这些变化与特定潜伏期范围内的事件相关电位变化有关。这些发现支持了这样一种观点，即在皮层处理的早期，空间特异性注意力选择机制可以根据传入感觉信号的空间位置来调节它们，并且可能独立于高阶刺激形式。
