The Effect Of Spatial Distance Between Bi-target On Attention Distributed Mode

Numerous studies have shown that the distribution of attentional focus is extremely flexible.It can move quickly among multiple targets,and also focus on more targets in different spatial locations synchronously.Studies have confirmed that the switching or changing on the distribution of attentional focus can be affected by many factors,such as task difficulty and presented time.However,the spatial distance between the targets as a key factor affecting the attention allocation,whether it will affect the spatial distribution of attentional focus,has not been confirmed.In order to explore this problem,this study used a fast-presenting dual-target discrimination task and set both vertical and horizontal targets.By controlling the spatial distance between the two targets as farther or closer,we can observe the influence of vertical targets on horizontal target reflected on the N2 pc components.In Experiment 1,the distance levels of either farther or closer were completely randomized.The ERP results showed that the later amplitude of N2 pc under farther-distance conditions was significantly smaller than the closer distance condition.It indicated that farther distance caused the subject to be unable to achieve the attentional focus separated.However,whether top-down attentional regulation will affect the distribution of attention focus is not known.In Experiment 2,the farther and closer distances were presented in Block design,which regulated top-down attention by controlling the subject's expectation of spatial position.The ERP results were identical to those of Experiment 1.This showed that attentional focus separation was not affected by top-down regulation.Subsequently,Experiment 3 further verified the difference in attention processing modes between the farther and closer conditions by increasing the masking stimulus.The behavioral results showed that there was no significant difference in accuracy between the two distances when the masking stimulus was absent,and the accuracy of farther distance was significantly lower than that of closer distance when the masking stimulus was presented.In summary,the present study showed that,in the rapid presentation,the attention allocated pattern was affected by the spatial distance between targets.The longer distance hindered the attentional focus separation in the parallel attention,and switched it to the sequential attention.Moreover,under long-distance condition,subjects may complete targets searching and discriminated tasks through the sensory memory.