As indicated by the Adams research placing mem­ory in a social context, in many situations, older adults perform quite well at memory tasks. In addi­tion, a number of cognitive reserve factors, such as IQ, educational level, occupation, and activity levels, may enhance cognitive functioning as we grow older (Scarmeas & Stern, 2003; Valenzuela & Sachdev, 2006). Cognitive reserve involves factors that lessen cognitive decline in that they provide flexibility in responding and adapting to changes in the environment (Buckner,

2004) . Let’s investigate some of these conditions.

Exercising Memory. One approach to cognitive res­erve is to view memory as a mental muscle. By applying this approach, older adults should benefit from repetitive practice, which involves using spe­cific memory exercises. Exercising memory on one type of task strengthens it, setting the stage for better memory in a variety of other tasks (Colcombe & Kramer, 2003). For example, practicing how to orga­nize a grocery list over and over will help one learn to organize other kinds of lists as well. Similarly, both physical and mental activity may serve as a protec­tive factor against memory decline in later life. In fact, reduction in activity has been correlated with decline in cognitive performance (Mackinnon et al., 2003). Fitness training also has increased cognitive performance in older adults regardless of the train­ing method or the older adults’ personal character­istics (Colcombe & Kramer, 2003). Recall that we examined this phenomenon in Chapter 2 by show­ing that physical exercise has effects at a biological level on the structure and functioning of the brain.

Multilingualism and Cognitive Functioning. In a recent study, Kave and colleagues (2008) explored whether the number of languages a person speaks positively influences the cognitive state of older adults. In fact, older adults from 75 to 95 years of age who spoke four languages or more showed the best cognitive state. This suggests that multilingualism might be a protective factor for maintaining our cognitive state as we age. Interestingly, it did not matter whether the individuals had high or low education—speaking many languages had the same protective effect. The authors suggest that knowledge of many languages

214 CHAPTER 6 might reflect an innate flexibility in using brain struc­tures, thus serving a proxy role for brain reserve.

Semantic Memory in Service of Episodic Memory. Given that semantic memory is relatively unimpaired as we grow older (as discussed earlier), it may have an enhancement effect on episodic memory for older adults. Accordingly, Verhaeghen and colleagues (1993) found that many studies have shown that the ability to group to-be-remembered episodic information into previously learned semantic cat­egories reduces age differences on such memory tasks. Similarly, a number of studies have shown that older adults perform better when they can use previously learned semantic information to support episodic knowledge (Naveh-Benjamin, Craik, Gues, & Kreuger, 2005). For example, older adults are bet­ter at memory for related as opposed to unrelated word pairs (Naveh-Benjamin, 2000).

Negative Stereotypes and Memory Performance. A

number of studies have demonstrated factors that can negatively influence memory performance in older adults. As a result, the elimination of such factors could enhance memory functioning in older adults. A primary example under investigation is negative stereotypes of aging. Briefly, older adults may not perform at optimal levels because they are aware of and threatened by the typical belief that aging hampers memory ability (Levy, 1996; Hess, Auman, Colcombe, & Rahhal, 2003). We will further explore this psychosocial factor influenc­ing cognition in Chapter 8. At this point, be aware that a wealth of factors have been positively and negatively associated with older adults’ memory functioning beyond cognitive mechanisms such as working memory, speed of processing, and encod­ing and retrieval abilities. In the next section, we explore two more factors in depth: self-evaluations of memory and memory training.

Concept Checks

1. Why is task complexity important in prospective memory?

2. What factors help preserve memory? What factors hamper memory?