Serial Position Markers in Space: Visuospatial Priming of Serial Order Working Memory Retrieval

Most general theories on serial order working memory (WM) assume the existence of position markers that are bound to the to-be-remembered items to keep track of the serial order. So far, the exact cognitive/neural characteristics of these markers have remained largely underspecified, while direct empirical evidence for their existence is mostly lacking. In the current study we demonstrate that retrieval from verbal serial order WM can be facilitated or hindered by spatial cuing: begin elements of a verbal WM sequence are retrieved faster after cuing the left side of space, while end elements are retrieved faster after cuing the right side of space. In direct complement to our previous work—where we showed the reversed impact of WM retrieval on spatial processing—we argue that the current findings provide us with a crucial piece of evidence suggesting a direct and functional involvement of space in verbal serial order WM. We outline the idea that serial order in verbal WM is coded within a spatial coordinate system with spatial attention being involved when searching through WM, and we discuss how this account can explain several hallmark observations related to serial order WM.

绝大多数关于系列顺序工作记忆（Working Memory, WM）的通用理论均假定，存在一类位置标记，此类标记可与待记忆项目绑定，从而实现对序列顺序的追踪。迄今为止，此类标记的确切认知与神经特征仍未得到充分阐明，且其存在的直接实证证据也极为匮乏。本研究证实，言语系列顺序工作记忆的信息提取可通过空间线索提示实现易化或干扰：当对空间左侧进行线索提示时，言语工作记忆序列的起始项提取速度更快；而对空间右侧进行线索提示时，末尾项的提取速度则更为迅捷。本研究直接补充了我们此前的工作——此前我们曾证实工作记忆提取对空间加工存在反向影响——我们认为，本次研究结果为"空间直接且功能性地参与言语系列顺序工作记忆"这一观点提供了关键证据。我们提出了如下构想：言语工作记忆中的序列顺序是以空间坐标系进行编码的，且在工作记忆中进行检索时需要空间注意的参与；此外，我们还探讨了该理论框架如何解释一系列与系列顺序工作记忆相关的标志性观测结果。