New Experiments

Experiment 1

This experiment was a variation of Rendell et al. (2007, Experiment 1), but rather than asking participants to write down the names of the faces, we asked them to write down the occupations of the faces. The focal target cue was a particular occupation (politician), whereas the nonfocal cue was the presence of eyeglasses on the face. As in Rendell et al., to examine possible trade-offs between the prospective and ongoing tasks, we compared participants' performance on the ongoing task in the prospective memory groups with performance on the ongoing task in control groups that performed only the ongoing task.

Fourteen younger and 14 older adults were assigned to each of the prospective memory conditions (focal vs. nonfocal cues). In addition, 18 younger and 18 older adults were assigned to the control condition in which participants performed only the ongoing task. The younger adults (undergraduates from the University of New Mexico) ranged in age from 18 to 46 years (M = 21.5). The older adults (from the greater Albuquerque, New Mexico, area) ranged in age from 63 to 86 years (M = 73.5).

The proportions of successful prospective memory responses (out of eight trials) are displayed in Figure 7.1 as a function of age group and type of prospective memory cue (focal, nonfocal). As can be seen, the focal cue produced substantially higher performance than the nonfocal cue (Ms = .86 vs. .42), but prospective memory levels did not significantly differ as a function of age (Ms = .66 and .62 for younger and older adults, respectively). This finding was not modulated by the type of cue, as the absence of age differences was observed for both the focal and nonfocal cues.

Focal Nonfocal

FIGURE 7.1 Mean proportion of correct responses on the prospective memory task (out of a possible eight) in Experiment 1. Error bars represent standard errors of the mean.

Focal Nonfocal

FIGURE 7.1 Mean proportion of correct responses on the prospective memory task (out of a possible eight) in Experiment 1. Error bars represent standard errors of the mean.

To shed light on the possible explanations outlined earlier for the absence of age deficits in prospective memory, we examined performance on the ongoing activity. Control group performance on the ongoing activity was used as a baseline against which to gauge the degree to which the ongoing activity performance declined in the presence of the prospective memory task. We scored the proportion of correct responses for the occupation identification task, and Figure 7.2 gives the mean proportions for the experimental and control groups. In general, performance was worse for older adults than for younger adults. Inspection of Figure 7.2 indicates

Focal Nonfocal Control

FIGURE 7.2 Mean proportion of the correct occupations identified (out of a possible 120) in Experiment 1, according to prospective memory condition (Control = no prospective memory task). Error bars represent standard errors of the mean.

Focal Nonfocal Control

FIGURE 7.2 Mean proportion of the correct occupations identified (out of a possible 120) in Experiment 1, according to prospective memory condition (Control = no prospective memory task). Error bars represent standard errors of the mean.

that the decline for older adults occurred in both the prospective memory and the control conditions. Thus, even without prospective memory demands, this occupation identification task was harder for older adults. Whether the age decrement was knowledge based (i.e., older adults knew fewer of the occupations for the famous faces) or whether it was based on retrieval difficulties (e.g., retrieval demands of the task disfavored older adults), or both, is not certain.

The critical issue for purposes here, however, concerns how performance on the occupation identification task fared for each age group in the presence of focal cue and nonfocal cue prospective memory demands relative to performance when prospective memory was not required (the control group). Statistical analyses revealed that for younger adults performance on the occupation task did not significantly decline with the addition of either type of prospective memory task. Likewise, for older adults with a focal prospective memory cue, performance on the ongoing activity (M = .75) did not decline relative to performance in the no-prospective memory control (M = .73). By contrast, with a nonfocal cue, older adults showed a significant drop in performance on the occupation identification task (M = .64) relative to the no-prospective memory control.

These results are again consistent with the multiprocess framework (McDaniel & Einstein, 2000; see also Maylor et al.'s, 2002, task-appropriate processing view). When the prospective memory task was signaled by a cue that is focal to the processing of the ongoing activity, there were no significant age differences in prospective memory performance. More critically, we found no costs to the occupation identification activity for older (and younger) adults when the prospective cue was focal. The pattern thus converges on the theoretical position that with focal cues, prospective memory retrieval can be relatively automatic (McDaniel & Einstein, 2000) and therefore exhibits minimal or no age-related decline.

Another new finding was that older adults maintained prospective memory performance at levels displayed by younger adults even when the prospective memory task used nonfocal cues. This result can be understood by the observation that older but not younger adults incurred significant expense to the ongoing activities in the presence of the nonfocal cue prospective memory task. In the next experiment we investigated whether a different set of older adults with different prospective memory and ongoing tasks would also operate with this particular trade-off (i.e., maintain prospective memory with nonfocal cues at the expense of the ongoing activity). We also used an ongoing activity that provided reaction times (a more telling index of cost; Smith, 2003) and relied on within-subjects comparisons to test for converging support for these patterns just reported.

Experiment 2

The ongoing activity was a category judgment task patterned after that used by Einstein et al. (2005, Experiment 2), who demonstrated that response latencies were sensitive to costs produced in conditions in which participants were explicitly encouraged to adopt monitoring strategies for the prospective memory task. The category judgment activity involved presenting a word and a category label, and participants were required to decide as quickly as possible whether the word was a category coordinate. In the focal cue condition, the target cue was a particular word (e.g., dormitory), whereas in the nonfocal cue condition the target cue was a syllable (e.g., tor). We measured each participant's attention allocated toward the prospective memory task by comparing the participant's accuracy and speed of performance on the ongoing task with and without the prospective memory task.

Two issues were of central interest. First, we wanted to see if older adults would again maintain levels of prospective memory performance at levels evidenced by younger adults even with demanding nonfocal cues. Second, we were interested in the age-related pattern of costs on the category judgment task produced in the focal cue and the nonfocal cue conditions. By most if not all views of prospective memory, in the nonfocal cue condition older adults should show poorer prospective memory performance or disproportionately more costs than younger adults, or both. Predictions start to diverge for the focal condition. The multiprocess framework (McDaniel & Einstein, 2000) anticipates no costs for either younger or older adults. By contrast, views assuming that capacity-demanding attentional processes are necessary for prospective remembering (e.g., Smith, 2003) predict significant costs to the ongoing activity for both younger and older adults in the focal cue condition accompanied by age-related decrements in prospective memory, disproportionate costs for older adults (given age-related declines in attentional resources; Salthouse, 1991b), or both.

There were 24 participants from each age group assigned to each condition (focal vs. nonfocal target). The younger adults were students at Furman University, ranging in age from 18 to 23 years (M = 20.29). The older adults lived in the Greenville, South Carolina, area and ranged in age from 68.6 to 82 years (M = 0). The younger and older participants were included from the outset of the experiment (i.e., tested during the same time period and by the same experimenters), however, the data from the younger participants have been reported for other purposes in Einstein et al. (2005). They are described here as baselines for evaluating age-related changes in prospective memory.

Table 7.2 provides the proportion of successful prospective memory responses as a function of target condition (focal, nonfocal), prospective memory trial (Trials 1-4), and age (younger, older). The results were entirely in line with Experiment 1. There was no significant difference between the prospective memory performance of younger adults and older adults (Ms = .77 and .72). Prospective memory performance was significantly better with the word (focal) target (M = .92) than with the syllable (nonfocal) target (M = .57), and this effect did not interact with age. In addition, prospective memory significantly declined by Trial 4 relative to the initial trials.3 Importantly, this decline over trials significantly interacted with the type of target. As can be seen in Table 7.2, prospective memory declined across trials for the syllable condition but not for the word condition.

Participants' accuracy on the category decision task was generally high (M = .97) and varied only slightly across conditions (see Table 7.3 for means). To

3 With trial as a variable, the prospective memory data are dichotomous (0, 1) for each cell. When degrees of freedom are not low (e.g., less than 20), as in this analysis, analysis of variance gives accurate results with such data (Rosenthal & Rosnow, 1991, p. 521).

TABLE 7.2 Mean Proportion Correct on the Prospective Memory Task in Experiment 2

Target Condition Age Group Quadrant Focal (Word) Nonfocal (Syllables)

TABLE 7.2 Mean Proportion Correct on the Prospective Memory Task in Experiment 2

Target Condition Age Group Quadrant Focal (Word) Nonfocal (Syllables)

Younger

Was this article helpful?

0 0

Post a comment