Control of bottom-up attention in scene cognition contributes to visual working memory performance.

Several studies have investigated the relationship between working memory and attention. However, most of the relevant studies so far investigated top-down attention; only a few have examined possible interactions between bottom-up attention and visual working memory. In the present study, we focused on the visual saliency of different parts of pictures as an index of the degree to which one's bottom-up attention can be drawn towards each of them. We administered the Picture Span Test (PST) to investigate whether salient parts of pictures can influence the performance of visual working memory. The task required participants to judge the semantic congruency of objects in pictures and remember specific parts of pictures. In Experiment 1, we calculated a saliency map for the PST stimuli and found that salient but task-irrelevant parts of pictures could evoke intrusion errors. In Experiment 2, we demonstrated that longer gazing time at target areas results in a higher probability of making correct recognition. In addition, frequent gaze fixation and high normalized scan-path saliency values in task-irrelevant areas were associated with intrusion errors. These results suggest that visual information processed by bottom-up attention may affect working memory.