The Relationship between Short- and Long-Term Memory Is Preserved across the Age Range.

Both short- and long-term memories decline with healthy ageing. The aims of the current study were twofold: firstly, to build on previous studies and investigate the presence of a relationship between short- and long-term memories and, secondly, to examine cross-sectionally whether there are changes in this relationship with age. In two experiments, participants across the age range were tested on contextual-spatial memories after short and long memory durations. Experimental control in stimulus materials and task demands enabled the analogous encoding and probing for both memory durations, allowing us to examine the relationship between the two memory systems. Across two experiments, in line with previous studies, we found both short-term memory and long-term memory declined from early to late adulthood. Additionally, there was a significant relationship between short- and long-term memory performance, which, interestingly, persisted throughout the age range. Our findings suggest a significant degree of common vulnerability to healthy ageing for short- and long-term memories sharing the same spatial-contextual associations. Furthermore, our tasks provide a sensitive and promising framework for assessing and comparing memory function at different timescales in disorders with memory deficits at their core.

When Natural Behavior Engages Working Memory.

Working memory (WM) enables temporary storage and manipulation of information,1 supporting tasks that require bridging between perception and subsequent behavior. Its properties, such as its capacity, have been thoroughly investigated in highly controlled laboratory tasks.1-8 Much less is known about the utilization and properties of WM in natural behavior,9-11 when reliance on WM emerges as a natural consequence of interactions with the environment. We measured the trade-off between reliance on WM and gathering information externally during immersive behavior in an adapted object-copying task.12 By manipulating the locomotive demands required for task completion, we could investigate whether and how WM utilization changed as gathering information from the environment became more effortful. Reliance on WM was lower than WM capacity measures in typical laboratory tasks. A clear trade-off also occurred. As sampling information from the environment required increasing locomotion and time investment, participants relied more on their WM representations. This reliance on WM increased in a shallow and linear fashion and was associated with longer encoding durations. Participants' avoidance of WM usage showcases a fundamental dependence on external information during ecological behavior, even if the potentially storable information is well within the capacity of the cognitive system. These foundational findings highlight the importance of using immersive tasks to understand how cognitive processes unfold within natural behavior. Our novel VR approach effectively combines the ecological validity, experimental rigor, and sensitive measures required to investigate the interplay between memory and perception in immersive behavior. VIDEO ABSTRACT.