The functional role of visual working memory

Visual working memory (VWM) is usually studied using explicit memory tasks that obviously require maintaining information over a delay, emphasizing the “memory” part of “visual working memory.” However, the term “working memory” was originally developed to stress the role of short-term information storage in performing cognitive tasks that do not have explicit or obvious memory requirements. Here, we describe why a memory buffer may be needed for even the simplest cognitive operations, making an analogy between VWM and the memory registers inside the central processing unit of a conventional computer. We then present new evidence demonstrating that VWM is used for extremely simple tasks such as pressing a button when a specific shape is perceived. Finally, we propose that the use of VWM for such tasks reflects the challenges involved in flexibly routing perceptual inputs to motor outputs on the basis of task instructions, making a link between VWM and the central attention mechanism that has been studied in the psychological refractory period task.