Age differences in proactive interference in verbal and visuospatial working memory

Abstract

The current study examined the benefit of reducing proactive interference in verbal and visuospatial working memory tasks in young (25–30 years), young–old (65–75 years), and old–old (older than 75 years) adults. To reduce proactive interference, the verbal and visuospatial working memory tasks were administered in an ascending (the shortest lists presented first) or in descending (the longest lists presented first) format. Results showed that whereas old–old adults benefit from decreased exposure to proactive interference in working memory independently from the task content, young–old adults benefited only in the verbal task, and young adults did not show any benefit. Overall, these findings suggest that the ability to resist proactive interference in working memory tasks depends on the task content and is particularly impaired in late adulthood.

Keywords:

• Ageing
• Proactive interference
• Working memory

Notes

¹As suggested by one of the reviewers, the verbal and visuospatial WM tasks were also scored using the partial-credit unit-weighted (PCU) scoring procedure suggested by Conway et al. (2005). The PCU scores were highly correlated with the mean number of information correctly recalled (for verbal WM task, r=.98; for visuospatial WM task, r=.96). As a consequence, the results of the analyses did not change when they were run using the PCU scores in both verbal and visuospatial WM tasks.

²ANCOVA analyses with educational level as covariate on the measures used showed that this did not affect performance.