目的：探究相似的视觉工作记忆内容如何影响视觉知觉的判断与编码。
方法：利用双稳态的运动恢复结构(Structure From Motion, SFM)视觉刺激，观察前序非歧义版本的运动恢复结构刺激对一定ISI间隔后的的运动恢复结构(Structure From Motion, SFM)视觉刺激知觉的偏移影响。 利用非歧义-延迟-歧义刺激的范式，衡量知觉记忆的精度(歧义刺激的感知与非歧义方向一致)。视觉工作记忆的任务要求被试汇报非歧义与歧义刺激旋转速度差异，与歧义刺激旋转方向。注意任务要求被试回报歧义与非歧义刺激旋转方向。
结果：在实验一中，被试被要求观察利用非歧义-延迟-歧义刺激，完成注意的任务（条件一），或视觉工作记忆的任务（条件二）。结果表明，视觉工作记忆任务可以显著增强被试对非歧义刺激对歧义刺激知觉的偏移(p <0.01)。实验二中，刺激的延迟时期后半段呈现一个干扰刺激，通过fMRI实验中常用的MT+定位刺激，干扰延迟时期视觉工作记忆内容在MT+皮层的表征。结果表明，干扰刺激显著干扰非歧义刺激对歧义刺激知觉的偏移(p<0.001), 同时不影响视觉工作记忆的能力。(p=0.58)
结论：视觉工作记忆会增强知觉记忆的影响，体现在视觉工作记忆能够增强前序非歧义刺激对后续歧义刺激感知的影响，这种知觉记忆与知觉皮层(MT+)对视觉工作记忆内容的表征有关。
其他摘要
PURPOSE: To understand how similar VWM content affects encoding and representation of coming up visual stimulus and why an unambiguous prior stimulus can cause an ambiguous stimulus to be perceived in the same way.
METHODS: We hypothesize that the prior unambiguous SFM can evoke a pre-activation representation in MT+ and affect the representation of the coming up ambiguous SFM, and holding it into visual working memory could enhance such effect. To test this hypothesis, we carry out two behavioral experiments. In the first experiment, subjects are asked to watch a serial of unambiguous SFM-delay-ambiguous SFM with two tasks, one for attending only and another for holding the rotation speed of the unambiguous SFM into the working memory. The second experiment is performed toimpair the pre-activation representation in MT+. We present distractors to reduce the pre-activation representations in MT+ during the delay period. We use visual stimulus in MT+ localizer run to maximize the active MT+ activity and also, impair the pre-activation representation.
RESULTS: In the experiment 1, results show that the visual working memory tasks could strengthen the perceptual bias of unambiguous SFM significantly (p< 0.01). In the experiment 2, results show that with distractors presented, the perceptual bias level will be greatly impaired (p< 0.001), but at the same time, the VWM accuracy is little affected (p= 0.58).
CONCLUSION: Our results suggest that the perceptual bias phenomenon is closely related to the persist pattern representations in MT+ evoked by VWM.
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