Is there a reduction in serial order working memory abilities in healthy aging?

The preservation of the ability to maintain information over the short-term in healthy aging remains a controversial question. Here we focused on one of the most challenging aspects of verbal working memory (WM), the ability to not only maintain verbal events but to also maintain their serial order of occurrence. An immediate serial recall task was administered to 30 young adults (18-30 years) and 30 older adults (60-80 years). Participants had to recall sequences of words or nonwords, from 2 to 7 items per sequence. They were matched for level of education and verbal intellectual efficiency Bayesian statistics showed moderate evidence for an absence of group effect for the total number of items recalled irrespectively of the items’ serial position (BF01 = 3,25 for words, BF01 = 1,26 for nonwords). When also scoring serial position information, we observed anecdotal evidence in favor of a group effect (BF10 = 2,9 for words; BF10 = 0,5 for nonwords). These results suggest that if there is a reduction of verbal WM abilities in healthy aging, it is very small and limited to the maintenance of serial order information.