Differential effects of age on prospective and retrospective memory tasks in young, young-old, and old-old adults

Abstract

Remembering to do something in the future (termed prospective memory) is distinguished from remembering information from the past (retrospective memory). Because prospective memory requires strong self-initiation, Craik (1986) predicted that age decrements should be larger in prospective than retrospective memory tasks. The aim of the present study was to assess Craik's prediction by examining the onset of age decline in two retrospective and three prospective memory tasks in the samples of young (18–30 years), young-old (61–70 years), and old-old (71–80 years) participants recruited from the local community. Results showed that although the magnitude of age effects varied across the laboratory prospective memory tasks, they were smaller than age effects in a simple three-item free recall task. Moreover, while reliable age decrements in both retrospective memory tasks of recognition and free recall were already present in the young-old group, in laboratory tasks of prospective memory they were mostly present in the old-old group only. In addition, older participants were more likely to report a retrospective than prospective memory failure as their most recent memory lapse, while the opposite pattern was present in young participants. Taken together, these findings highlight the theoretical importance of distinguishing effects of ageing on prospective and retrospective memory, and support and extend the results of a recent meta-analysis by Henry, MacLeod, Phillips, and Crawford (2004).

Keywords:

• Prospective memory
• Retrospective memory
• Ageing and memory
• Young-old
• Old-old

Acknowledgements

It is with great regret that we have to inform readers of the recent death of Alan Milne. He will be sadly missed.

Research presented in this paper was supported by a grant from the Economic and Social Research Council to Lia Kvavilashvili, Diana Kornbrot, Janet Cockburn and Alan Milne. Portions of research described in this paper were presented at the 1st International Conference on Prospective Memory in July 2000 (University of Hertfordshire), the Experimental Psychology Society Meeting in January 2001 (University College London), and the Psychonomic Meeting in November 2002 (Kansas City). We are grateful to Fiona Kyle for helping us to collect data and to young and old volunteers who took part in the study. The assistance of the University Medical Centre in recruiting volunteers is also gratefully acknowledged.

Notes

¹Kvavilashvili and Ellis (1996) have also distinguished activity-based tasks that involve remembering to do something before or after finishing a certain activity, for example, taking a pill after the breakfast (see also Harris, 1984). Because these tasks do not involve the interruption of ongoing activity, as something is to be done during the “gap” between the two consecutive activities, Kvavilashvili and Ellis (1996) have suggested that activity-based tasks may be easier to remember than event- and time-based tasks both of which usually require the interruption of ongoing activity.

²Since the variable for remembering the red pen was binary, a more sensitive logistic regression analysis was also conducted. As with ANOVA, there was a significant main effect of age group χ ² (2)=15.1, p=.002, with a modest effect size (Nagelkerke r ² =.10). However, post hoc comparisons resulted in a significant difference between young and young-old, χ ² (1)=12.5, p=.0004, and marginally significant difference between young-old and old-old, χ ² (1)=3.3, p=.068.

³A similar pattern has also been obtained with the Everyday Memory Questionnaire by Martin (1986) as older adults scored better on prospective memory items (keeping appointments, paying bills, and taking medications), and younger adults on retrospective items (remembering names, telephone numbers, and sports results). However, other questionnaire studies (see e.g., Dobbs & Rule, 1987; Smith, Della Sala, Logie & Maylor, 2000) did not obtain any differences between prospective and retrospective items as a function of age. This could be due to problems that older adults may have when trying to retrospectively evaluate the frequency of different types of memory failures experienced in everyday life. In this respect, asking participants to recall their most recent failure can substantially reduce demands on retrospective memory and produce more valid results.

⁴For example, “What is the telephone number for Directory Enquiries?” Answers: 999, 192, 129, 555, or “What is the lowest value coin used in public telephones?”: 1p, 2p, 5p, 10p.

⁵A question about available processing resources is not properly solved even when young and old participants have similar performance levels on the ongoing activity. This is because older adults may need to put more effort (available attentional resources) into ongoing tasks than young to maintain similar levels of performance (cf. Kvavilashvili & Fisher, 2007).