Characterizing adult age differences in the initiation and organization of retrieval: A further investigation of retrieval dynamics in dual-list free recall

In a recent experiment using dual-list free recall of unrelated word lists, C. N. Wahlheim and M. J. Huff (2015) found that relative to younger adults, older adults showed: (a) impaired recollection of temporal context, (b) a broader pattern of retrieval initiation when recalling from 2 lists, and (c) more intrusions when selectively recalling from 1 of 2 lists. These findings showed older adults' impaired ability to use controlled retrieval to avoid proactive and retroactive interference. In the present investigation, 3 studies examined whether differences in retrieval initiation patterns were unique to aging and whether they were governed by the control mechanisms that underlie individuals' susceptibility to intrusions. In Study 1, we conducted additional analyses of Wahlheim and Huff's data and found that older adults' broader retrieval initiation when recalling 2 lists was a unique effect of age that was not redundant with intrusions made when recalling from individual lists. In Study 2, we replicated these age differences in a dual-list paradigm with semantically associated lists. In Study 3, we found that older adults' broader retrieval initiation generalized when they were given twice the encoding time compared with Study 2. Analyses of transitions between recalls in Studies 2 and 3 showed that older adults used temporal associations less than younger adults, but both groups made similar use of semantic associations. Overall, these findings demonstrate adult age differences in the controlled retrieval of temporal context in hierarchically structured events.