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Cautiousness and VisualSelective AttentionPerformance Among OlderAdultsMichael C. Rush a , Paul E. Panek b & Joyce E. A.Russell aa Department of Management , University ofTennessee - Knoxville , USAb Department of Psychology , Eastern IllinoisUniversity , USAPublished online: 02 Jul 2010.

To cite this article: Michael C. Rush , Paul E. Panek & Joyce E. A. Russell (1987)Cautiousness and Visual Selective Attention Performance Among Older Adults, TheJournal of Genetic Psychology: Research and Theory on Human Development, 148:2,225-235, DOI: 10.1080/00221325.1987.9914552

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Journal of Genetic Psychology, 148(2), 225-235

Cautiousness and Visual Selective Attention Performance Among Older Adults

MICHAEL C. RUSH Department of Management

University of Tennessee - Knoxville

PAUL E. PANEK Department of Psychology Eastern Illinois University

JOYCE E. A. RUSSELL Department of Management

University of Tennessee - Knoxville

ABSTRACT. Cautiousness has been implicated in the literature as a possible factor responsible for observed performance decrements among older adults in a number of research paradigms. This study sought to assess whether the speed and accuracy of performance on a perceptual-cognitive task (the Stroop Color-Word Interference Test) differed significantly for more and less cautious older adults. The participants (N = 41). ranging from 55 to 8 1 years of age, were classified as either more cautious (n = 20) or less cautious ( n = 21) on the basis of their responses on a personality test. Results indicated that cautiousness among older adults was manifested more in terms of the accuracy of response (fewer errors of commission) than in terms of the speed of response, and that level of cautiousness increased with increasing age.

THE SPEED AND ACCURACY of performance of older adults on percep- tual-cognitive tasks such as the Stroop Color-Word Interference Test (Stroop, 1935) has been the focus of considerable attention in the adulthood and aging

Requests for reprints should be sent to Michael C . Rush, Department of Manage- ment, University of Tennessee, Knoxville, TN 37996.

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226 Journal of Generic Psychology

literature (e.g., Brinley, 1965; Dyer, 1973; Panek, Rush, & Slade, 1984). Due in part to the ease of administration, as well as the nature of the required responses, the Stroop test has been used in a number of studies to investigate various issues in the areas of memory and cognition, perception, retrieval, and selective attention (see Burke & Light, 1981; Comalli, Wapner, & Wer- ner, 1962; Dyer, 1973; Jenson & Rohwer, 1966). Although varied, the re- search has generally focused on the color-word interference effect and its im- plications.

In brief, the Stroop test requires the respondent to name the color of ink in which a word is printed. When the word is a color name different than the ink color (e.g., the word “BLUE’ printed in green ink), the speed of the color naming response tends to be significantly slower than the speed of the re- sponse when the word and ink color correspond or when the individual is simply asked to name the color of a series of color patches. This Stroop (color-word) Interference effect is generally attributed to problems associated with trying to read the base word, cognitively processing and retrieving its name, while trying to process and retrieve the color name at the same time (Burke & Light, 1981). Thus, the mixed-stimulus condition is thought to evoke two mutually exclusive responses that interfere with each other, result- ing in a delayed response (Dyer, 1973; Posner, 1978).

Individual differences in response times on the three cards associated with the Stroop test, as well as in the magnitude of the interference effect per se (i .e., delayed response) have been reliably and consistently demonstrated in the literature (Dyer, 1973). With regard to age effects, older adults have been shown to exhibit significantly slower color naming responses in the mixed-stimulus condition than do younger adults, as well as significantly larger interference effects (i.e., the age-Stroop interference effect; Burke & Light, 198 1). Interestingly, only marginal differences have been reported be- tween younger and older adults in terms of the speed of response for naming the ink color of color patches and for reading the names of color words written in black ink.

Numerous explanations have been offered for the age-Stroop interference effect (see Brinley, 1965; Comalli et al., 1962; Kausler, 1970; Panek et al., 1984; Welford, 1958), and most interpretations suggest that the dispropor- tional slowing response is somehow associated with age changes in the speed of cognitive functioning (e.g., orthogenetic principle, response-competition, response-competition with failure to selectively attend, manifest difficulties in encoding and retrieval processes). Despite the plausability of these inter- pretations, each must be viewed as only partially successful in explaining the phenomenon because large portions of variance remain unexplained (Burke &Light, 1981).

One possible explanation for the age-Stroop interference effect that has received little attention concerns the effect of dispositional trait factors. In

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Rush, Panek, & Russell 227

particular, the avoidance of risk or greater cautiousness on the part of older adults may play a significant role in the age decrements observed on a number of laboratory and “real world” tasks (Schaie & Gribben, 1975). In terms of the Stroop task, older adults may, in general, exhibit a more cautious ap- proach (i.e., slower response time) to the mixed-stimulus condition than do younger adults in order to avoid making overt errors in response. In fact, research suggests that the older adult’s performance on a variety of tasks is frequently characterized by an increased number of errors of omission rather than errors of commission (Okun, 1976; Okun, Siegler, & George, 1978).

Empirical support for the effects of cautiousness among older adults has been quite varied and is apparently contingent upon the particular criterion variable investigated in the study, the employed definition of cautiousness, and the method of assessing cautiousness, among other factors (see Botwin- ick, 1978; Harkins, Chapman, & Eisdorfer, 1979; Okun, 1976; Okun et al., 1978; Panek & McGown, 1981). The sheer complexity of the construct sug- gests that the method of assessment may be a critical factor.

Measuring cautiousness on the basis of exhibited task performance, as is done in many studies, may provide only an indirect assessment of what many consider to be a personality-behavioral characteristic or trait (Panek & Mc- Gown, 1981). In effect, performance-based measures tend to confound a trait-state distinction that may be relevant to many areas of inquiry. As an alternative, personality assessment techniques could provide a more appro- priate measure of cautiousness as a personality-behavioral characteristic. In particular, projective techniques, which have served as a traditional method of assessing personality characteristics for individuals across all phases of the life cycle, may be quite suitable for the purpose.

Though many of the projective techniques currently available have been criticized as inappropriate for use with older adults (Kahana, 1978), one tech- nique, the Hand Test (Wagner, 1962), has satisfactorily addressed many of the criticisms (see Panek, Wagner, & Kennedy-Zwergel, 1983). Further, the High-Minus-Low score from the Hand Test has been interpreted as a probable measure of cautiousness in the normal population (Wagner, 1962, pp. 24- 25).

The purpose of the present study was to examine whether there are any significant differences between more and less cautious older adults, identified via projective techniques, in terms of their speed and accuracy of perform- ance on the Stroop test. Available literature suggests that more cautious, rel- ative to less cautious, older adults could be expected to (a) exhibit signifi- cantly slower response times, particularly on the interference card (Card C), and (b) commit significantly fewer errors on the Stroop test. Further, if cau- tiousness is a reasonable, albeit partial, explanation for the interference ef- fect, the predicted effects should hold regardless of any probable age differ- ences between the two groups.

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228 Journal of Genetic Psychology -

Method

Participants

Participants were 41 community-living older adults, ranging from 55 to 81 years of age (M = 65.37, SD = 6.66). All of the participants, 56% of whom were women, reported being in good or excellent health, were within the normal range of verbal intellegence as assessed with the Quick Test IQ (Am- mons & Ammons, 1962a, 1962b; M = 134.27, SD = 21.66), and had at- tained an average of 12.53 years of formal education (SD = 3.47). In effect, the participants constituted a reasonable sample of normal, healthy, function- ing older adults.

Procedure

All participants were administered the Stroop Test (Stroop, 1935) and the Hand Test (Wagner, 1962) according to standard procedures outlined for each instrument. The Stroop test was identical to that employed by Comalli et al. (1962), and Panek et al. (1984). The task consists of three kinds of stimuli, printed on 23.5 cm by 23.5 cm cards. The first card (A) consists of 100 color words (red, blue, and green) printed in black ink and randomly arranged in 10 lines of 10 items. The subject’s task is to read each of the color words as fast as possible. The second card (B) consists of 100 rectangular color patches (lcm x 4cm; red, blue, and green), which are to be named as quickly as possible. The third and final card (C) presents, again in random order, 100 color words (red, blue, and green). This time however, the words are printed in an ink whose color is different than the color designated by the word (e.g., the word red printed in blue ink). The subject’s task is to name the color of ink in which the word is printed as quickly as possible. Total response time in seconds and number of errors committed on each card were recorded for each participant as they moved through the cards in consecutive order.

The High-Minus-Low score from the Hand Test was used as an index of the participant’s level of trait cautiousness. The Hand Test consists of 10 cards, 9 of which portray hands in various ambiguous positions. The tenth card is blank. The subject’s task is to describe “what the hand could be doing.” The High-Minus-Low (H-L) score represents the time differential be- tween an individual’s slowest (high) and fastest (low) initial response time to any of the test stimuli. Scores ranging from 4 to 30 s are not unusual in the normal population, and a small difference between the slowest and fastest response time (a low H-L score) has been interpreted as a relative lack of caution or circumspection on the part of the individual in responding to the novel stimuli constituting the test (Wagner, 1962, pp. 24-25).

For purposes of the present study, individuals were classified as either

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more or less cautious (greater than or less than 6.4 s, respectively) based on a median split of the sample distribution of H-L scores (M = 8.5 s, SD = 1.6 s), as there is no normative basis for classifying level of cautious- ness. Because of the resulting small cell sizes, the independent effect of gen- der also had to be ignored in the present study. Not unexpectedly, preliminary analyses revealed that the individuals classified as more cautious were signif- icantly older than the less cautious individuals (M age of 68.15, SD = 6.78 vs. M age of 62.71, SD = 5.46, respectively; r = 2 . 8 4 , ~ = .007). The two groups did not differ significantly (a = .lo) in either educational level or assessed verbal intellegence. The data thus permit relatively unconfounded tests of the predicted effects of cautiousness.

Results

Means and standard deviations for response time and number of errors com- mited on each of the three Stroop cards are presented in Table 1 by level of cautiousness. A comparison (directional independent r test) of more and less cautious older adults in terms of response times, before controlling for the differences in age, revealed that the more cautious subjects were significantly slower only in terms of responding to the color patches on Card B, r = 3.20,

TABLE 1 Mean Response Time and Errors on the Stroop Test for More

and Less Cautious Older Adults

All Less More Card adults cautious cautious t' E b t C

Response time (in seconds) A 45.76 (11.59) 44.71 (6.63) 46.85 (15.30) .59 .139 .38 B 67.46 (20.93) 61.91 (13.09) 73.30 (25.92) 3.20* .663 1.25 C 136.24 (39.39) 131.62 (36.99) 141.10 (42.16) S O 2.280* .25

Response errors A .42 (.77) .71 (.96) .10 (.31) -7.51** -.010 -2.51** B 1.85 (1.94) 2.57 (1.96) l.lO(1.65) -6.71** -.032 -2.89** C 3.05 (3.81) 4.19 (4.45) 1.85 (2.60) -4.18' -.071 -2.39**

NOTE. Standard deviations are indicated in parentheses. .T value for directional test comparing more cautious ( n = 20) to less cautious (n = 21) response. bunstandardized regression coefficient for age. 'Tvalue for directional test comparing more cautious to less cautious response, controlling for age. *p < .05 (one-tailed). **p < .01 (one-tailed).

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230 Journal of Genetic Psychology

p = .041, one-tailed. This difference in color naming response time was ef- fectively eliminated, however, when the difference in chronological age be- tween the two groups was statistically controlled, t = 1.25, ns. An analysis of covariance (ANCOVA) revealed that age of the participant was also signif- icantly related to response time on Card C, t = 2.28, p = .026, replicating several earlier studies.

A similar comparison of the two groups in terms of the number of errors committed on the Stroop Test revealed that the more cautious older adults committed significantly fewer errors than did the less cautious subjects on each of the three cards, even when the differences in age between the groups were taken into account (see Table 1). Analyses also suggest that the number of errors committed on any of the three cards was unrelated to the partici- pant’s age.

While the results seem to offer partial support for the predicted relation- ships, the pattern of results is curious in one sense. As previously noted, chronological age is a reliable predictor of an individual’s response time on the interference card (Card C), and, in fact, was significantly related to re- sponse time in the present sample of older adults. There was no evidence, however, that response time on Card C varied significantly for more and less cautious older adults, even though they differed significantly in chronological age. This pattern of results suggests that relative to the more cautious sub- jects, the less cautious subjects were exhibiting longer response times on the interference card than would be expected on the basis of their chronological age. A number of post hoc analyses were conducted to explore this issue, as well as to explore differences in the Stroop interference effect per se.

The Stroop Test can be viewed as three distinct tasks presented in a fixed repeated measures design (i.e., word reading, Card A; color naming, Card B; color naming with word interference, Card C). The difference in response time to Card C relative to Card B is traditionally viewed as an index of the Stroop interference effect. Similarly, the difference in response times for Cards B and A can be viewed as an index of the strength of the color naming response relative to the word reading response. Analyses reported in Table 2 were designed to explore whether these within-person effects varied for more and less cautious older adults, with an expectation that, after controlling for age, the less cautious adults would exhibit a significantly larger Stroop inter- ference effect than would more cautious adults. The analyses are based on a mixed-model analysis of variance involving one between-subject factor (cau- tiousness) and one within-subject factor (card response) partitioned as two nonorthogonal, repeated contrasts (B vs. A, and C vs. B) with age as a co- variate.

Analysis of response times as repeated measures, prior to controlling for age differences, revealed the expected pattern of results (see Table 2). For all subjects, regardless of level of cautiousness, response time for color naming

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232 Journal of Genetic Psychology

with word interference (Card C) was slower than for color naming without interference (Card B), t = 8.18, p < .01, and the color naming response on Card B was slower than the word reading response on Card A, t = 17.28, p < .01. Neither of these effects differed significantly for more or less cau- tious older adults. As suspected, however, the Stroop interference effect was somewhat larger (although only marginally so) for the less cautious individ- uals than for the more cautious individuals when the differences in age were taken into account, c = - 1.52, p = ,067.

A similar analysis (see Table 2) for consecutive errors commited on the Stroop Test, ignoring age differences, indicated that the less cautious adults committed significantly more errors across all three cards than did the more cautious adults, t = - 2.72, p < .01, and that all individuals, regardless of level of cautiousness, committed significantly more errors in color naming (Card B) than in reading the color words on Card A, r = 4.90, p < .01. Further, the difference in the number of errors committed on Cards A and B was relatively more pronounced for the less cautious than for the more cau- tious older adults, t = - 1.62, p = .057. The data in Table 2 also indicate that the pattern of response errors remained the same when the differences in age were taken into account.

Discussion

Despite possible limitations (e.g., limited sample size, pan-gender effects, single task and single measure of cautiousness), the results of the present study seem to offer some potential insight concerning the speed and accuracy of performance of older adults on perceptual-cognitive tasks. To briefly re- count, the results of the study suggest that the effect of cautiousness among older adults is, for the most part, manifested more in terms of the accuracy of response than in terms of the speed of response and that expressed cau- tiousness (as measured herein) increases significantly with increasing age. Analyses of the number of errors committed on the Stroop Test confirmed the hypothesis that less cautious older adults would commit a greater number of errors on each of the three Stroop cards than would more cautious adults, even after differences in age were taken into account. In contrast, analyses controlling for differences in age revealed no significant differences between more and less cautious older adults in terms of response time on any of the three Stroop cards.

The analyses also revealed an apparent paradox with respect to response time in that less cautious older adults seemed to exhibit a longer response time on the interference card (Card C), relative to more cautious adults, than would be expected on the basis of their younger age. Post hoc analysis of the within-person effects for response times, controlling for the differences in age, subsequently revealed that the less cautious adults did exhibit a some-

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what larger Stroop interference effect than the more cautious adults, given the relative difference in the length of the color naming response without inter- ference. The data seem to suggest a sort of opposing-process phenomenon in which the relative advantage in response time afforded younger, less cautious adults on the interference card is offset by a tendency to commit significantly more errors of commission, resulting in an objectively longer response time than would be expected on the basis of their uninhibited color-naming ability.

An opposing-process phenomenon appears reasonably consistent with recent emphasis on the role of encoding, retrieval, and memory processes in relation to the difficulties manifested by older adults on many perceptual- cognitive tasks (Kausler, 1970; Burke & Light, 1981). Although explanations involving processing speed are problematic for many reasons (Hartley, Har- ker, & Walsh, 1980), not the least of which is significant individual differ- ences, the emphasis basically suggests that older adults tend to experience increasing difficulties in encoding novel and unexpected stimulus situations and in retrieving appropriate but known responses when under pressure (Brin- ley, 1965; Burke & Light, 1981). Unfortunately, little attention has been de- voted to understanding how these effects are moderated by dispositional fac- tors.

Although speculative, the results suggest that the more cautious older adults may have encoded and retrieved the stimulus information at a more deliberate and consistent pace, simply by virtue of their disposition, and thereby avoided making excessive errors of commission. In contrast, the less cautious adults, again by virtue of disposition, may have either failed to at- tend closely to the stimulus situation or processed and retrieved stimulus in- formation in a faster and more superficial fashion, hence committing a greater number of errors. The increased response time under interference conditions may come about because the less cautious older adults initially encode the stimulus information quickly and superficially, retrieve an initial response, recognize the response as incorrect, superficially search for another response, and so on, before actually vocalizing their final response.

Naturally, further research and replication is needed before any firm con- clusions can be drawn. The results of the present study, while intriguing, should be viewed as exploratory. The size of the sample and the nature of the measure employed, among other factors, prohibit anything but tentative ac- ceptance. It is interesting to note, however, that the High-Minus-Low score (difference in initial response times) derived from the projective Hand Test (Wagner, 1962), though unrelated to the speed of performance, was related in a theoretically meaningful fashion to the accuracy of performance on the Stroop Test, a fact which seems to offer additional support for the construct validity of the score. Certainly, further investigations of dispositional factors, such as cautiousness, in relation to cognitive processes and speed and accu- racy of performance is warranted. If studied within segments of the life span

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as well as across the life span, the findings of such investigations may offer a more complete understanding of effects typically associated with changes in the speed of cognitive functioning.

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