Differential Transfer Effects Across Tasks in Younger and Older Adults Following Executive Function Training

Cognitive training can help improve cognition and build cognitive reserve in seniors, but the extent to which cognitive training leads to improvement in untrained tasks, the so called transfer effect, is still debated, and age-related difference in this matter remain understudied. This study investigated the effect of two executive function training tasks, the dual-task and the n-back task, on their analogous untrained tasks in 35 younger adults and 49 older adults. Performance was assessed before and after each group had completed 6 h of their respective training program spread over four weeks. Results show improvement in the dual-task transfer task after dual-task training in both younger and older adults, and that dual-task performances also improved after n-back training but only in older adults. Improvement in performance on the n-back transfer task was also observed after both trainings for the moderate task load (2-back), while for the higher load (3-back) the improvement was only observed in the n-back training group, with equivalent training effects in older and younger adults. These results suggest that executive function training can lead to near transfer to a non-trained task tapping the same attentional control process, in addition to showing age-related difference in transfer effect across tasks. This suggests that, while performing executive control tasks, older adults may engage different attentional control processes from the one targeted by the task. Indeed, improvement in dual-task performance after n-back training in older adults implies that improved working memory capacity can help older adults to better manage dual-task situations.