Going Shopping and Identifying Landmarks: Does Collaboration Improve Older People's Memory?

SUMMARY Older participants (mean age ¼ 72.82 years) attempted to recall items from shopping lists while shopping in a supermarket and subsequently in their homes on recognition tests. They also attempted to identify local landmarks on a map. The recall occurred either together with their spouses or independently. Collaborative recall was compared to the pooled, nonredundant recall of spouses who completed the memory tasks alone (nominal groups). Nominal groups produced more hits on most measures and never fewer hits than did collaborative groups. However, collaborative groups consistently generated fewer memory errors than did nominal groups. In many everyday contexts, a tendency for collaboration to reduce false recall could be advantageous to older people. Signal detection analyses revealed that collaboration leads couples to require a higher level of certainty before they are willing to claim that they recognize an item. Finally, we examined the relation between expertise and recall in the shopping and landmark tasks. Copyright # 2004 John Wiley & Sons, Ltd. Memory decline in later adulthood is particularly evident for episodic recall of where and when events happened, spatial memory (e.g. memory of the location of city landmarks), and specific facts such as the names of people (Craik, 2000; Zacks, Hasher, & Li, 2000). Although psychologists consider these forms of remembering to be individual cognitive activities, remembering is frequently collaborative in everyday life. Families and other social groups possess collective memories (Halbwachs, 1950). No individual can recall the total shared experience of the group without help from other people. Similarly, spouses depend on each other’s memories as they try to remember phone numbers, the location of a theatre, or the items they intend to buy at the supermarket (Wegner, Erber, & Raymond, 1991). Researchers suggest that older people can use collaboration to counteract agerelated declines in individual memory (e.g. Dixon, 1999; Gould, Osborn, Krein, & Mortenson, 2002). In the current study, we examine collaborative memory in older couples. Although there are many previous studies of collaborative memory, most have been conducted with university students on standard laboratory tests of recall. The findings are clear and reliable: Two heads are better than one in that two people, remembering together, recall more than either individual would recall alone. This effect has been demonstrated