Abstract: This study investigated the dynamic brain mechanisms of the visual spatial attention scale under the different attention scale. The immobile cues of three different sizes were used to eliminate the effect of the spatial location factor. The simple reaction time (RT) and event-related potentials (ERPs) was recorded. The results were that the RT to the targets under the same cue prolonged when the targets far away from the center, the target evoked P1 and N1 components were not affected by the targets location, while the amplitudes of the anterosuperior N2 showed targets location effect. The RT to the targets in the same location shortened when the cue size enlarged, the target evoked P1 and N1 were not affected by the attention scale factor, while the amplitudes of the inferoposterior P2 enlarged when the attentive region size enlarged. The results suggested that ① targets evoked P2 component was related to the processing of visual scale attention, ② the P1 and N1 components under visual attention were not involved in the attention scale, but related to the attention location processing mainly, ③ the visual scale attention was adjusted in a certain extent.

Key words: visual spatial attention, location cue, attention scale, adjust mechanism, event-related potentials (ERPs)