State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, PR China.
Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, PR China.
PLoS Biol. 2024 Jul 15;22(7):e3002721. doi: 10.1371/journal.pbio.3002721. eCollection 2024 Jul.
The abundance of distractors in the world poses a major challenge to our brain's limited processing capacity, but little is known about how selective attention modulates stimulus representations in the brain to reduce interference and support durable target memory. Here, we collected functional magnetic resonance imaging (fMRI) data in a selective attention task in which target and distractor pictures of different visual categories were simultaneously presented. Participants were asked to selectively process the target according to the effective cue, either before the encoding period (i.e., perceptual attention) or the maintenance period (i.e., reflective attention). On the next day, participants were asked to perform a memory recognition task in the scanner in which the targets, distractors, and novel items were presented in a pseudorandom order. Behavioral results showed that perceptual attention was better at enhancing target memory and reducing distractor memory than reflective attention, although the overall memory capacity (memory for both target and distractor) was comparable. Using multiple-voxel pattern analysis of the neural data, we found more robust target representation and weaker distractor representation in working memory for perceptual attention than for reflective attention. Interestingly, perceptual attention partially shifted the regions involved in maintaining the target representation from the visual cortex to the parietal cortex. Furthermore, the targets and distractors simultaneously presented in the perceptual attention condition showed reduced pattern similarity in the parietal cortex during retrieval compared to items not presented together. This neural pattern repulsion positively correlated with individuals' recognition of both targets and distractors. These results emphasize the critical role of selective attention in transforming memory representations to reduce interference and improve long-term memory performance.
世界上干扰物的丰富性对我们大脑有限的处理能力构成了重大挑战，但人们对选择性注意如何调节大脑中的刺激表示以减少干扰并支持持久的目标记忆知之甚少。在这里，我们在选择性注意任务中收集了功能磁共振成像 (fMRI) 数据，其中不同视觉类别的目标和干扰图片同时呈现。要求参与者根据有效线索选择性地处理目标，要么在编码期之前（即感知注意），要么在维持期（即反射注意）。第二天，参与者在扫描仪中进行了记忆识别任务，其中目标、干扰项和新项以伪随机顺序呈现。行为结果表明，与反射注意相比，感知注意更能增强目标记忆并减少干扰记忆，尽管整体记忆容量（目标和干扰记忆的总和）相当。通过对神经数据的多体素模式分析，我们发现感知注意在工作记忆中目标表示更强，干扰表示更弱。有趣的是，与反射注意相比，感知注意部分将参与维持目标表示的区域从视觉皮层转移到顶叶皮层。此外，与不在同一时间呈现的项目相比，在感知注意条件下同时呈现的目标和干扰项在检索期间在顶叶皮层中的模式相似性降低。这种神经模式排斥与个体对目标和干扰项的识别均呈正相关。这些结果强调了选择性注意在改变记忆表示以减少干扰和提高长期记忆表现方面的关键作用。
