Decoding the impact of aging on the interaction between visual attention and working memory.

Working memory (WM) is a temporally structured process with three subprocesses: encoding, maintenance, and retrieval. Encoding is essential for information entry into WM, particularly under limited processing resources, and is closely tied to visual attention, which selectively gates items into WM. This study examines the interaction between visual attention and WM across the lifespan, focusing on age-related changes. Using a delayed-match-to-sample task to assess WM, we tracked eye movements to analyse attentional deployment during encoding. Our results replicate previous findings of age-related declines in task performance and WM capacity, attributable to less thorough scrutiny of memory sets and diminished benefit from fixating on subsequently queried items among older participants. Task difficulty exacerbates these declines, with performance collapsing when memory loads exceed WM capacity -a pattern that begins around age 55 and becomes pronounced in later life. These results emphasise the crucial role of visual attention in WM encoding and its age-related modulation. Furthermore, our findings call into question the strict binary distinction between sequential and simultaneous processing, suggesting that serial effects in WM might emerge even under conditions of simultaneous presentations.