The Spatial Effect In The Course Of Visual Search

visual search is a basic information processing ability of every individual, and is regarded as one of the typical models in the field of attention. In the course of visual search, there are unevenly distributions in the attention space, namely, the spatial effect. The research primarily applied the technical combinations of eye movement recording and reaction time methods, with the view to track down the spatial effect based on the quadrant and eccentricity of simple, complex feature search and conjunction search as well. The results indicate that, according to three experiments, (1) in the task of visual search, there are hardly any time differences in target detecting based on the quadrant and eccentricity in pre-attention phase, in a word, no spatial effect found. (2) There are obvious spatial effects of attention allocations in the phase of attention. As a reflection, they could be mirrored not only in the distributions of attention in different quadrants, but also seen in the quadrant differences on the level of attention decoding. It is generally accepted that the amounts of distribution of lower visual fields are superior to the upper and the right is superior to the left. Therefore, the differences in the second quadrant are overwhelmingly predominant, whatever, smaller in the attention allocations and attention decoding. (3) in the task of visual search, the source of differences comes variously in terms of the target RT difference which stands in the different spatial sequence. However, in the task of feature search, it results from the sequence of the search. While in the task of conjunction search, it comes from the free non-sequential search errors caused by the information in the phase of pre-attention.