University of Wisconsin-Madison, Madison 53719, Wisconsin.
Lawrence University, Appleton 54911, Wisconsin.
eNeuro. 2024 Feb 9;11(2). doi: 10.1523/ENEURO.0270-20.2024. Print 2024 Feb.
Content-to-context binding is crucial for working memory performance. Using a dual-serial retrocueing (DSR) task on oriented gratings, Yu et al. (2020) found that content (orientation) of both prioritized and unprioritized memory items (PMI; UMI) was represented simultaneously in visual cortex, while their context (location) was represented in intraparietal sulcus (IPS), with a priority-based remapping of the representation of content and context of the UMI in each region, respectively. This registered report acquired fMRI of 24 healthy adults while they performed a DSR task with location as the to-be-reported content and orientation as the task-relevant context. We contrasted three accounts: domain-dependent, the engagement of visual and parietal regions depends on the feature domain (orientation vs location); functional, the engagement of these regions depends on their function (content vs context); and hybrid-a combination of the domain-dependent account and the additional stipulation that IPS encodes context regardless of domain. Delay-period activity in early visual cortex conformed most closely with functional predictions: robust priority-sensitive representation of stimulus location (content), but no evidence for the active representation of stimulus orientation (context). Delay-period activity in IPS, in contrast, conformed most closely to predictions of the hybrid account: active representation of content (location) and of prioritized context (orientation). Exploratory analyses further supported the hybrid account of IPS, revealing univariate sensitivity to variation in both content and context load, the latter in a manner that predicted individual differences in behavior. The representation of visual information in working memory is highly dependent on behavioral context.
内容到上下文的绑定对于工作记忆表现至关重要。Yu 等人(2020 年)使用定向光栅的双序列回溯(DSR)任务发现,优先和非优先记忆项目(PMI;UMI)的内容(方向)同时在视觉皮层中表示,而其上下文(位置)则在顶内沟(IPS)中表示,分别在每个区域中以基于优先级的方式重新映射 UMI 的内容和上下文的表示。这项注册报告获得了 24 名健康成年人的 fMRI,他们在执行 DSR 任务时,位置是要报告的内容,方向是任务相关的上下文。我们对比了三种解释:领域依赖,视觉和顶叶区域的参与取决于特征领域(方向与位置);功能,这些区域的参与取决于其功能(内容与上下文);混合-领域依赖解释和 IPS 无论域如何都编码上下文的额外规定的组合。早期视觉皮层的延迟期活动与功能预测最吻合:刺激位置(内容)的强大优先级敏感表示,但没有刺激方向(上下文)的主动表示的证据。相比之下,IPS 的延迟期活动最符合混合解释的预测:内容(位置)和优先上下文(方向)的主动表示。探索性分析进一步支持 IPS 的混合解释,揭示了对内容和上下文负荷变化的单变量敏感性,后者以预测行为个体差异的方式。工作记忆中视觉信息的表示高度依赖于行为上下文。