The rise and fall of memories: Temporal dynamics of visual working memory.

Abstract

Visual working memory (VWM) is a cognitive system, which temporarily stores task-relevant visual information to enable interactions with the environment. In everyday VWM use, we typically decide how long we look to encode information, and how long we wait before acting on the memory. In contrast, VWM is typically studied in unnaturally rigid paradigms that keep presentation times and delays fixed. Here, we ask how visual memories build up over self-paced viewing times, and how they decay over self-paced delays, in a task that naturally engages VWM. We employed a copying task in which participants were tasked to recreate an "example" arrangement of items in an adjacent empty "workspace". We tracked their unconstrained viewing and copying behavior at the level of individual items' viewing times and the time to successful placements (i.e., delay). Our results show that performance monotonically increased for viewing times up to 1 s (per item), and plateaued afterwards. Interestingly, while views exceeding 1 s did not strongly improve performance for short (2-s) delays, views beyond 1-s did improve performance for longer delays. In contrast, this pattern was not observed in Experiments 2A and 2B, where viewing and delay times were experimentally manipulated (i.e., in more typical, rigid paradigms). These findings showcase the importance of considering aspects of naturalistic behavior, like decision-making, when studying VWM. We suggest that in everyday situations, short glances are sufficient for immediate use from VWM, but long views are required for effective delayed use.