cern for time, punctuality, and planning activities in advance (Inkeles and Smith, 1974). The complexity of work roles has also been associated with general characteristics of cognitive functioning in adults (Kohn et al., 1978, 1982). Technology also shapes cognition through training. Abacus users have been found to make different kinds of errors in solving mathematical problems from people who use Arabic numerals (Stigler, 1984; Stigler et al., 1986). It has been argued that in medieval times, when few people could use writing as a memory aid, memory was much more detailed and rote than it is in advanced societies today (see Yates, 1966; Carruthers, 1990; Olson, 1994). And it has been suggested that television shapes a mind adept in rapid processing of images and comfortable with attending for repeated short periods rather than extended ones (Greenfield, 1984).

Following on reported differences in information processing styles between people from East Asian and European cultural groups (Hsu, 1983; Liu, 1974; Lloyd and Moodley, 1990; Nagashima, 1973), Park and colleagues (1999) found that cues in a memory task had different effects on people from the two groups. Compared with people from European cultures, supportive cues helped the East Asians more, and distracting cues harmed their performance more. The explanation offered was in terms of the previously published claim that memory among East Asians is more sensitive to contextual cues, whereas Europeans focus more narrowly on the object at hand. The same authors offered a contextual-support explanation for their finding that Americans perform better than Chinese on a free recall task involving six words from five natural categories.

A second set of causal hypotheses involves health as an intervening variable between social context and cognitive aging. A central idea is that the shared life experiences of certain social groups may lead them to suffer more from diseases like hypertension, cardiovascular disease, and diabetes that directly affect cognitive functioning (see Waldstein, Appendix E, for a discussion of these health effects). For example, people from lower-status social groups, including low-status ethnic minority groups, have poorer health histories, including a higher incidence of chronic diseases that have cognitive effects (Williams, 2000). Similarly, people lacking in social support—resources available through social ties to other individuals and groups—may suffer more from the effects of stress (Caplan, 1974; Cassel, 1976; Cobbs, 1976; Payne and Jones, 1987; Seeman et al., 1996) and experience negative effects on blood pressure and immune function (Uchino et al., 1996). Differences in social support may help account for poorer health outcomes among black Americans, although there are compensatory effects of cultural factors, such as religion (Jackson et al., 1995; Ortega et al., 1983), and the effects may be moderated by demographic variables such as socioeconomic status, marital status, age, and gender.

Another health-related explanation of group differences in cognitive func-



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