Older adults require more time than younger adults to receive, store, process, and retrieve information (Cavanaugh & Blanchard-Fields, 2010; Findsen & Formosa, 2011; Gembris, 2012; Lengrand, 1975; Mast et al., 2009). Primary cognitive abilities, including fluency with words and numbers, inductive reasoning, and spatial orientation, can begin to decline after age 60, with this decline becoming more pronounced after the mid-70s. However, an overarching decline is not evident for all secondary cognitive abilities, which are associated with fluid and crystallized intelligence, generation of new ideas, visual and auditory intelligence, memory, and cognitive speed. Some types of secondary cognitive abilities decline with age, while others can actually improve (Cavanaugh & Blanchard-Fields, 2010; Coffman, 2002a; G. D. Cohen, 2000). For example, fluid intelligence, or the ability to process information independently of previously acquired knowledge, is believed to develop early in life and decline significantly with age. This may reflect physiological age-related declines in psychomotor skills and sensory-perceptual abilities (Findsen & Formosa, 2011). On the contrary, crystallized intelligence, or culture-based knowledge that is acquired through education and life experience, generally remains constant or increases with age (Belsky, 1990; Cavanaugh & Blanchard-Fields, 2010; Coffman, 2002a; G. D. Cohen, 2000; Findsen & Formosa, 2011; Jaeggi, Buschkuehl, Jonides, & Perrig, 2008). This likely happens because new information is acquired at a rate that equals or exceeds the rate at which information is forgotten (Findsen & Formosa, 2011). However, even though crystallized intelligence involves cultural knowledge, its ability to function is based partially on fluid intelligence. For example, the breadth of someone’s vocabulary depends to some extent on the speed with which he or she can make connections between new words and information that was already acquired (Cavanaugh & Blanchard-Fields, 2010). It is worth noting that even though older adults do experience some decline in fluid intelligence, they are often able to compensate for this by increasing their level of expertise or knowledge in a particular area (G. D. Cohen, 2000). Attentiveness and memory in cognitive processing are two areas that many researchers have studied.
Attentiveness. As adults become older, they become less efficient in the processes used to maintain attention (Findsen & Formosa, 2011; Mast et al., 2009). For example, older adults may report that their minds wander while reading and they then have to go back and reread something, or that they sometimes begin one task at home and get unintentionally distracted into doing something else. Research shows that age has only a mild effect on the basic processes of attending to a stimulus, selecting relevant information, and filtering out other nonrelevant information. On the contrary, degenerative changes in attention processes that require higher levels of energy and cognitive resources become more pronounced with age, such as attending to more than one task simultaneously (commonly referred to as multitasking) or searching through a number of possibilities to target a selection (Blanchet, Belleville, & Peretz, 2006; Findsen & Formosa, 2011).
Memory. Decline or loss of memory is stereotypically and negatively associated with aging; however, not all older adults are affected by memory decline. Those who do experience memory problems are usually not affected in the same way or to the same degree. Deficits in memory tend not to be associated with specific components of the memory process (such as encoding, storing, or retrieving), but instead occur throughout the cognitive process. However, age-related declines in memory become substantial in instances in which higher levels of cognitive resources and processing are required to purposefully remember (Findsen & Formosa, 2011).