Abstract: Using circles and squares as visual targets and 400 Hz and 1200 Hz tone pip as auditory targets, the present study explored the different effect of attention on multisensory integration by directing the attention to different modality to form two conditions of attention. The results showed that only in the condition of divided attention, the response accuracy was significantly higher and RTs were significantly shorter for bimodal targets than either visual or auditory targets. It showed a processing advantage for the bimodal targets only when the attention was divided between two modalities, the so-called redundant signal effect. To account for the redundant signal effect, the distributions for bimodal responses were compared to the race model. We compared the distribution of bimodal responses to the joint probability of visual and auditory responses using paired t-tests. The result showed that responses probabilities were significantly higher for bimodal targets than the race model probabilities at time between 310 and 490ms when participants divided their attention between visual and auditory targets. We found that the redundant signal effect of bimodal targets in the divided attention condition arose from the multisensory integration. In one word, the multisensory integration occurred when the attention was divided between visual and auditory modality.

Key words: divided attention, selective attention, multisensory integration, the race model

摘要： 以简单图形为视觉刺激，以短纯音作为听觉刺激，通过指导被试注意不同通道（注意视觉、注意听觉、注意视听）以形成不同注意状态（选择性注意和分配性注意），考察了注意对多感觉整合的影响，发现只有在分配性注意时被试对双通道目标的反应最快最准确。通过竞争模型分析发现，这种对双通道目标的加工优势源自于视听双通道刺激的整合。上述结果表明，只有在分配性注意状态下才会产生多感觉整合。

关键词: 分配性注意, 选择性注意, 多感觉整合, 竞争模型。