Tata Matthew S, Alam Nazia, Mason Aja L O, Christie Gregory, Butcher Andrew
The University of Lethbridge, 4401 University Drive, Lethbridge AB T1K 3M4, Canada.
Vision Res. 2010 Apr 7;50(8):750-60. doi: 10.1016/j.visres.2010.01.012. Epub 2010 Jan 25.
Attended stimuli typically evoke larger event-related potentials (ERPs) than unattended stimuli. We previously reported an exception when an optic-flow pattern is interleaved with stationary dots. Reversals of motion direction evoked a larger N200 peak when attention was directed to the stationary dots. We replicated and further characterized this result: the N200 enhancement was eliminated when the dots moved randomly rather than in optic flow. The effect was also attenuated with isoluminant stimuli. Electrical source analysis suggested the attentional modulation of a configuration of dorsal extrastriate generators. The ERP evoked by reversals of optic flow may reflect the operation of independently configurable attentional filters within visual cortex.
与未被注意的刺激相比，被注意的刺激通常会诱发更大的事件相关电位（ERP）。我们之前报道过一个例外情况，即当光流模式与静止点交错出现时。当注意力指向静止点时，运动方向的反转会诱发更大的N200峰值。我们重复并进一步描述了这一结果：当点随机移动而不是以光流形式移动时，N200增强效应消失。等亮度刺激也会减弱这种效应。电源分析表明，背侧纹外发生器配置存在注意力调制。光流反转诱发的ERP可能反映了视觉皮层内可独立配置的注意力过滤器的运作。
