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1 Facilitative and Inhibiting Effects of Distraction on Attitude Change Author(s): Chester A. Insko, William Turnbull and Ben Yandell Source: Sociometry, Vol. 37, No. 4 (Dec., 1974), pp Published by: American Sociological Association Stable URL: Accessed: :12 UTC Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at info/about/policies/terms.jsp JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. Sage Publications, Inc. and American Sociological Association are collaborating with JSTOR to digitize, preserve and extend access to Sociometry.

2 Sociometry 1974, Vol. 37 No. 4, Facilitative and Inhibiting Effects of Distraction on Attitude Change CHESTER A. INSKO WILLIAM TURNBULL BEN YANDELL University of North Carolina In a situation in which subjects listened to a persuasive communication while working on a task, they were told either to attend primarily to the communication (message set) or to the task (task set). There was, in addition, a message-only condition. Relative to the message-only condition, message set increased attitude change and communicationfavorable thoughts, and decreased number of counterarguments and recall. Relative to the message-set and message-only conditions, task set decreased attitude change, recall and effort attending to the communication. On the basis of these results it was argued that different mediational models are operating for message-set distraction and task-set distraction. Specifically, it was proposed that message set produces a causal chain running from an increase in communication-favorable thoughts to a decrease in counterarguments to an increase in attitude change. On the other hand, it was proposed that task set decreases attitude change partially through a consistency-achieving devaluation of the interfering communication, and partially through a large decrement in recall. Application of Blalock's method of testing causal hypotheses with correlational data was used to illustrate the theoretical models. As a variable in attitude change research, distraction involves a division of attention between a persuasive communication and communication-irrelevant stimuli. The first experiment directly concerned with the effect of distraction on persuasion was done by Festinger and Maccoby (1964). In two of three experiments they found that subjects who watched a distracting movie while listening to an anti-fraternity communication were more persuaded by the communication than were subjects who listened to the same communication while watching a movie of the actual speaker. According to Festinger and Maccoby, the distracting movie 508

3 EFFECTS OF DISTRACTION ON ATT ITUDE CHANGE 509 facilitated persuasion by interfering with the usual process of counterarguing. Unfortunately, subsequent research has not produced consistent results. Some studies (e.g., Haaland and Venkatesan, 1968) have found that distraction decreases persuasion and some studies (e.g., Osterhouse and Brock, 1970) have found that distraction increases persuasion. In their extensive review of this literature, Osterhouse and Brock noted that when the major arguments contained in the message were recalled equally well by distracted and nondistracted subjects, distracted subjects exhibited greater attitude change than nondistracted subjects. This suggests that in order for distraction to facilitate persuasion, the distracting stimulus should not be of sufficient magnitude to interfere with learning of communication content. What is the crucial aspect of the distraction manipulation that produces differential recall results? Zimbardo et al. (1970) stress that the subject's perception of what is "message" and what is "distraction" may well differ from the experimenter's perception. When a subject is primarily oriented toward the persuasive communication, he or she should be able to recall or comprehend the major points of that communication. Zimbardo et al. refer to this as a message set. When, on the other hand, the subject is primarily oriented toward the task, he or she should be less able to comprehend the communication. For this task set, the communication is the distraction, and the task is the "message." In their experiment Zimbardo et al. used a persuasive communication advocating the shortening of college summer vacations to one month and a task which involved totaling the number of letters, rather than the numerical sum, in the names of two digits, such as "one plus one = 6." They had three conditions: message set, task set, and message only (with no distraction). After a number of unsuccessful attempts to manipulate set, they succeeded in obtaining the expected results. More influence occurred in the message-set condition than in the message-only condition, and nonsignificantly less influence occurred in the task-set condition than in the message-only condition. On the other hand, recall of the communication was approximately the same in the message-set and message-only conditions, and significantly less in the task-set condition. Distraction only facilitated persuasion when it did not decrease comprehension or recall. Such results are gratifying. Zimbardo et al. may have finally identified the appropriate distraction manipulation necessary to

4 510 SOCIOMETRY produce a facilitative effect on persuasion. We are still left, however, with no satisfactory explanation as to why a message set should facilitate persuasion. Certainly the absence of differences in recall between message-set and message-only conditions is not a sufficient explanation. In view of the failure of their assessments of counterarguing, recall, and effor to parallel the obtained results for attitude, Zimbardo et al. view the situation as a challenge to existing theories of attitude change and a possible indication that the attempt to understand attitude change in terms of mediational processes is futile. What are some of the possible mediators of the effect of distraction upon attitude change? First, there is Festinger and Maccoby's suggestion regarding counterarguing. They maintain that when a person who is strongly committed to his position encounters a persuasive message active counterarguing occurs. To quote directly: Certainly, such a listener is not passive. He does not sit there listening and absorbing what is said without any counteraction on his part. Indeed, it is most likely that under such circumstances, while he is listening to the persuasive communication, he is very actively, inside his own mind, counterarguing, derogating the points the communicator makes, and derogating the communicator himself. In other words, we can imagine that there is really an argument going on, one side being vocal and the other subvocal (1964: 360). Distraction facilitates persuasion by reducing the opportunity for counterargument. Evidence consistent with Festinger and Maccoby's hypothesis was obtained by Osterhouse and Brock (1970). They used a post-communication thought-listing technique to assess counterarguing and found, in two separate studies, both that distraction decreased counterarguing and, more important, that covarying the number of counterarguments made the effect of distraction upon attitude change nonsignificant. On the other hand, Zimbardo et al. found that subjects' post-communication estimates of the time spent counterarguing were not significantly affected by message-set distraction. In contrast to the contention that counterarguing mediates attitude change, Miller has argued that counterarguing is mediated by attitude change. He is justifiably concerned with the potentially reactive nature of the thought-listing procedures used by Brock and others. It is possible that the experimenter's request that the subject list his thoughts will result in products that would not have spontaneously occurred. To quote Miller:... counterarguing may be a rationalization process, a post-persuasion

5 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 511 technique used to justify whatever position one finds oneself holding. In other words, it may not be a mechanism for resisting influence. If observed differences in counterarguing do stem from rather than cause differential attitude change, the theoretical explanations that invoke counterarguing become worthless (1971: 12). A second possible mediator of the effect of distraction upon attitude change is retention of communication content. Perhaps the best known of the attempts to account for attitude change via mediation by retention is Miller and Campbell's (1959) theory of primacy-recency. More relevant to the present context, however, is McGuire's (1966) observation that a learning theory approach to distraction predicts that when the distraction produces a decrement in learning, the persuasive impact of the communication should be lessened. As noted above, Osterhouse and Brock observed that when the distraction did not interfere with learning there was an increase in persuasion. However, when distraction does interfere with learning, there may actually be a decrease in persuasion (cf. Haaland and Venkatesan, 1968). A third possible mediator of the effect of distraction upon attitude change is effort-producedissonance. From a dissonance perspective it could be argued that the effort expended attending simultaneously to a communication and a distraction produces dissonance which is reduced through increased agreement with the position advocated in the communication. By agreeing with the communication the subject justifies the previous expenditure of effort. The same argument could be made from an attribution perspective. As previously indicated, however, Zimbardo et al.'s assessment of effort attending to the communication did not parallel the attitude results. Effort ratings for the message-set, message-only and task-set conditions were 59, 70, and 28, respectively. Subjects reported exerting most effort attending to the message in the message-only condition-the condition that produced an intermediate amount of attitude change. Finally, Greenwald's (1967, 1968) thought-listing procedure provides an additional set of possible mediators. Subjects list their thoughts after exposure to the communication, and these thoughts are classified into three major categories; externally-originated, recipient-modified, and recipient-generated. Externally-originated thoughts are thoughts having their source in the communication or other experimental materials. Recipient-modified thoughts are reactions to, qualifications of, illustrations of, and deductions from the experimental materials. Recipient-generated thoughts are thoughts not traceable directly to the experimental materials (e.g., a

6 512 SOCIOMETRY general expression of values). Although Greenwald himself has not suggested that his thought indices are mediators of the distraction effect, the possibility is an obvious one. Of course, there should be some overlap between counterarguments and thoughts-particularly recipient-generated thoughts. The present investigation is intended as a further exploration of the possible mediational basis of the effect of distraction upon attitude. We feel that Zimbardo et al.'s distinction between message set and task set is an important contribution. We are, however, unable to accept their position with regard to the lack of mediation of obtained effects. We specifically hypothesize that the facilitative effect of message set upon attitude change is mediated by a reduction in counterarguments. It seems to us quite likely that Zimbardo et al. would have found a decrease in counterarguments if they had used the Brock-Greenwald thought-listing procedure rather than a rating of the time spent counterarguing. We believe that the theoretically important variable is the number of counterarguments, and number of counterarguments may or may not be correlated with time spent counterarguing. What about the effect of task set on attitude change? We again believe that the effect upon attitude change, in this case an inhibiting effect, is not without mediation. It is fairly obvious, however, that number of counterarguments is not a likely mediator. Thus we suspect that the facilitative effect of message set upon attitude change and the inhibiting effect of task set upon attitude change have different mediational bases. The theoretically important factor in the present experiment is a three-level manipulation of set (message set, message only, and task set). The data, in these levels or conditions are examined from the standpoint of two orthogonal contrasts, message set and task set. The message-set contrast is a comparison of the message-set and message-only conditions. The task set contrast is a comparison of the task-set condition with the mean of the message-set and message-only conditions. The message-set factor is included in a design using Zimbardo et al. 's communication and distracting task.1 The important differences between the studies are in the present study's inclusion of additional assessments and in the analysis of the result. In addition to Zimbardo 1We wish to thank Philip Zimbardo for supplying us with copies of the persuasive communication and dependent variable assessments used by Zimbardo et al., We also wish to thank Allan Lind for tape-recording the communication.

7 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 513 et al.'s assessments of recall and effort, the thought-listing procedure is used to obtain assessments of counterarguing and each of Greenwald's three types of thought. The novel aspect of our data analysis involves an adaptation of Blalock's (1964) procedure for testing causal models with correlational data. Finally, we should mention that in order to investigate some hypotheses regarding individual differences, subjects were blocked according to whether they were external-internal (Schopler, personal communication, 1972) and were normals, fats, or thins (cf. Schachter, 1971). Since none of the individual difference hypotheses were supported, there will be no discussion of them. METHOD Subjects The subjects were 218 male introductory psychology students at the University of North Carolina who participated in the experiment in partial fulfillment of a course requirement. The data from two additional subjects who failed to complete all of the assessments were eliminated. Independent Variables There were four independent variables: set, order of assessment, internal-external subjects, and thin-normal-fat subjects. The set manipulation had three levels: message set, message only, and task set. Message-only subjects simply listened to the persuasive communication. The message-set and task-set subjects simultaneously listened to the communication and worked on the number task. Message-set subjects were told that their primary task was to listen to the communication, and task-set subjects were told that their primary task was to work on the number task. Order of assessment was manipulated by assessing attitude before or after the thought listing. Finally, subjects were blocked according to whether they were above or below the experimental population mean on the internal-external dimension (Schopler, personal communication, 1972), and according to whether they were normals, fats, or thins according to Schachter's norms (cf. Schachter, 1971). There was, in addition, a no-communication control condition. 2Preliminary analyses indicated no significant differences due to experimenter, and, thus, experimenter was not used as a factor in any reported analyses.

8 514 SOCIOMETRY Procedure Two of the investigatorserved as experimenters. Subjects were randomly assigned to conditions, and insofar as each experimenter's schedule permitted, experimenters were randomly assigned to experimental sessions.2 Subjects were recruited in groups of six for an experiment on "Attitudes." Upon arriving they were individually sent to one of six separate small rooms. Here they were instructed on the use of the headphones and asked to fill out Form 1, which contained the internal-external scale and questions regarding the subject's height and weight. After finishing Form 1, subjects were instructed through the headphones to turn to Form 2, entitled "Speed of Summation Test." The experimenteread the instructions for the number task and asked the subjects to read along silently with him. Subjects were given five minutes to complete as many sums as they could. At the end of the five-minute period subjects were asked to stop working and turn to Form 3. As before, the experimenteread the instructions while the subjects read along silently. Form 3 contained Zimbardo et al.'s set manipulation. Following Zimbardo et al.'s example, after the subjects had been instructed as to a particular attentional set, they completed three questions assessing comprehension of, and thus re-emphasizing, the manipulation. Since pre-testing revealed that the subjects tended to focus on the number task regardless of the experimental instructions, the procedure was further modified to strengthen the message-set manipulation. After subjects completed the three questions, the experimenteread the correct answers and instructed subjects to erase any incorrect answers and write in the correct answer. In reading the correct answer, the experimenter always made reference to where the answer occurred in Form 3. At this point, task-set subjects were reminded that while their primary task was to do the number task, they must simultaneously listen to the tape-recorded communication. Messageset subjects, however, were reminded of their primary task (listening to the communication), but no further mention was made of the number task. After completing the set manipulation, the experimenter turned on the tape-recorded communication. The communication, which advocated the shortening of summer vacations to one month, is the same as that used by Zimbardo et al. While listening to the communication through the headphones, subjects simultaneously worked on the number-summation task. Message-only subjects

9 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 515 listened to the tape-recorded communication, but did not simultaneously work on the number task. At the conclusion of the tape recording, subjects were asked to complete Form 4 (which contained the dependent variable assessments). In the no-communication control condition subjects simply arrived at the laboratory, were segregated into the small rooms, and filled out the two attitude assessments. They did not hear the communication, nor did they fill out Forms 1 and 2. Dependent Variables As mentioned above, the various assessments were contained in Form 4. Two measures of attitude toward "reducing the college summer vacation to one month" were taken. One measure, obtained from Zimbardo et al., was a rating (on a 6-point scale) of disagreement-agreement with the reduction in summer vacation. The other measure was the sum of three (7-point) semantic-differential ratings (good-bad, wise-foolish, beneficial-harmful). On both assessments high numbers indicated a favorable attitude. Before or after making the above attitude ratings, subjects listed their thoughts as per Greenwald's (1968) procedure. When the subjects had finished the additional ratings described below they returned to their listed thoughts and judged them, first, as to their favorability to the advocated position, and second, according to whether they were externally-originated (communication thoughts), recipient-modified (reactions), or recipient-generated (own thoughts). Such ratings allowed for the construction of a favorable minus unfavorable index for each of the three types of thought. Greenwald's procedure of weighting and then dividing the weighted difference by the total number of thoughts was not used because of Calder, Insko, and Yandell's (1974) finding that such additional complexities did not improve the correlation with attitude. The thought data were also categorized by the experimenters in terms of Brock's (1967) concept of counterarguing. The categorization was done independently, but in those cases in which there was difficulty in making a decision, the experimenters conferred on the proper category for that thought. The remaining assessments of Form 4 were of effort exerted in listening to the communication, division of attention between the two tasks, time spent counterarguing, and communication recall. Effort exerted listening to the communication was assessed with a single 100-point rating scale ranging from "none" to "extreme amount." Division of attention between the two tasks was assessed

10 516 SOCIOMETRY by having subjects check one of the 11 percentage categories, ranging from written-100-auditory-o to written-0-auditory-100. This, of course, provided for a check on the set manipulation and was only taken in the message-set and number-set conditions. The final score is simply the percentage of time attending to the communication. Percentage of time spent counterarguing was assessed with a single rating scale ranging from "all listening" to "50/50" to "all arguing against." Communication recall was assessed with questions concerning the position of the communication (one point possible), number of arguments advanced (one point possible), what these arguments were (3 points possible) and how many arguments were elaborated (one point possible). Thus the final assessment had a range from 0 to 6. RESULTS MANOVA A four-factor (set, order, internal-external, fats-thins) least squares multivariate analysis of variance was performed on all the dependent variables. Due to the lack of any significant multivariateffects of order, internal-external, and fats-thins, no subsequent analyses are reported for these factors. The few significant univariate F's were scattered and uninteresting. Manipulation Check The means for the three set conditions, together with the relevant F's for the set main effect, are presented in Table 1. The number of observations in these cells varies between 62 and 64. As Table 1 indicates, the percentage of time attending to the communication varies significantly in the expected direction. The percentages are in the message-set condition and in the number-set condition. It is interesting to note that even with our repeated emphasis on the importance of attending to the communication, subjects in the message-set condition reported dividing their attention almost equally between the communication and task. A ttitude Both assessments of attitude toward shorter summer school vacations showed the expected results. Attitude was barely toward the favorable end of the scales in the message-set condition and most unfavorable in the task-set condition. As Table 1 indicates, the F's

11 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 517 TABLE 1 Mean Assessments in the Message Set, Message-only, and Task-Set Conditions Assessment Message Set Message Only Task Set F Attention to Comm., % ** Attitude rating ** Attitude semantic differential * Effort listening ** Recall ** Counterarguments * Counterarguing time, % Communicationfavorable thought ** E-O thought index ** R-M thoughts index R-G thought index *p <.05 **p <.01 for both assessments are significant. Orthogonal contrasts of message set with message only are significant for both the rating scale (F = 2.92, p <.05, one-tailed) and the sum of the semantic differentials (F = 3.32, p <.04, one-tailed). (Since the direction of this effect was predicted, on the precedent of Zimbardo et al.'s results, one-tail tests are appropriate.) Likewise, contrasts of task set with the mean of message set and message only are significant for both the rating scale (F = 6.42, p <.01, one-tailed) and the sum of the semantic differentials (F = 5.33, p <.02, one-tailed). What about results for the no-communication control? Mean attitude rating was 1.38, and mean semantic differential assessment was Both of these means differ from the comparable assessment in the task-set condition (F = 26.84, p <.001; F = 37.16,

12 518 SOCIOMETRY p <.001, respectively). Comparison was made with the task-set condition because this is the experimental condition in which the least amount of change occurred. Clearly, the experimental conditions produced attitude change. In the analyses described below, we consider each of the potential mediators of attitude (effort, recall, counterarguing, thoughts) in order. We will also note whether or not the results for the potential mediator parallel or do not parallel the attitude results for the message-set and task-set contrasts. Effort The main effect of set on effort exerted listening to the communication is highly significant (see Table 1). Orthogonal contrasts indicate that the comparison of message set with message only is not significant (F = 1.03), but the comparison of task set with the mean of message set and message only is significant (F = 40.53, p <.01). Subjects reported exerting less effort attending to the communication in the task-set condition than in the other two conditions, which do not differ from each other. These results, which are roughly comparable to those obtained by Zimbardo et al., suggest that a dissonance or attribution model cannot account for the facilitativeffect of message set upon attitude change. Message set increased attitude change but did not alter reported effort. A similar interpretation, however, does not hold for the task-set contrast. Task-set subjects reported spending less effort attending to the communication and were less persuaded by the communication. Such parallel results suggest that the inhibitory effect of task set upon attitude change is either mediated by effort or by one or more variables with which effort is correlated. Recall As indicated in Table 1, the main effect of set on recall is highly significant. Furthermore, both the message-set contrast (F = 29.84, p <.01) and the task-set contrast (F = 97.19, p <.01) are significant. Recall was less in the task-set condition than in the message-set and message-only conditions and less in the message-set condition than in the message-only condition. The recall means for the message-set contrast, however, do not parallel the attitude results where more change occurred in the message-set condition. It should be noted that these results do not agree with Osterhouse and Brock's generalization that distraction only facilitates persuasion when there is no interference with recall.

13 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 519 With regard to the task-set contrast, the means for recall and attitude parallel each other. There was less recall and less attitude change in the task-set condition. Thus recall, like effort, parallels the attitude-change results for the task-set contrast. Counterarguing As shown in Table 1, the set factor had a significant effect upon number of counterarguments. The message-set contrast is significant (F = 9.02, p <.01), but the task-set contrast is not (F =.06). Fewer counterarguments were produced in the message-set condition than in the other two conditions. The means for the message-set contrast are in agreement with expectations; that is, more attitude change and fewer counterarguments occurred in the message-set condition. Such results replicate Osterhouse and Brock's two studies, and, of course, are consistent with the mediational model originally proposed by Festinger and Maccoby. Due to an oversight, Zimbardo et al.'s assessment of time spent counterarguing was not taken in the message-only condition. As Table 1 indicates, however, the assessments in the message-set and task-set conditions have nonsignificantly differing means. Ratings of time spent counterarguing and number of counterarguments produced appear to be tapping different processes. Thoughts As can be seen in Table 1, the set main effect is significant for externally-originated thoughts but not for recipient-modified or recipient-generated thoughts. The externally-originated-thought index is the difference between the number of favorable and the number of unfavorable thoughts derived from the communication. Separate analyses of the communication-favorable and communication-unfavorable thoughts revealed a significant effect for the former (F = 9.67, p <.01), but not the latter (F = 1.13, n.s.). The effect for externally-originated thoughts is, in fact, an effect for communication-favorable thoughts. The means for communication-favorable thoughts are in Table 1. The message-set contrast for communication-favorable thoughts is significant (F = 17.71, p <.01), but the task-set contrast is not (F = 1.63, n.s.). There were more communication-favorable thoughts in the message-set condition than in the other two conditions. These

14 520 SOCIOMETRY results thus suggest a second mediator, in addition to counterarguments, for attitude change as a function of message set.3 DISCUSSION The results generally are in accord with expectations. With regard to the difference between message-set and message-only conditions there were three important effects: first, message set increased the amount of attitude change; second, message set decreased the number of counterarguments; and third, message set increased the number of communication-favorable thoughts. The results for attitude change are in agreement with prediction, and replicate Zimbardo et al. 's similar finding. The results for number of counterarguments are also in agreement with prediction. The results for communication-favorable thoughts were not specifically predicted, but do agree with our general bias regarding the importance of cognitive mediation. How are such effects to be interpreted? Message-set distraction produced three effects: increased attitude change, decreased counterarguments, and increased communication-favorable thoughts. It is, of course, quite possible that any number of causal sequences could give rise to this pattern of correlated effects. We, however, would like to hypothesize a causal chain from message-set distraction to increased communication-favorable thoughts to decreased counterargument to increased attitude change. We believe that this causal sequence makes a good deal of sense. When the subject mobilizes his cognitive resources to follow the communication content and incidentally to work on the task, communication-favorable thoughts are the one type of thoughts that allow for completion of the role assignment and possibly the only type for which the subject has time. It is certainly reasonable to suppose that, relative to the message-only condition, the subject would have minimal time for an active thought process such as counterarguing. In the message-only condition the subject does have time for counterargument, and the counterarguing process reduces the persuasive impact of the communication in that condition. Thus, relative to the message-set condition, the message-only condition produces a lesser persuasive impact. 3 One final result comes from the within cell correlations-most of which were small and uninteresting. Some readers may be interested in knowing that the within cell r's for counterarguments with the externally-originated, recipientmodified and recipient-generated thoughts were -.34, -.35, and -.67, respectively.

15 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 521 The above theoretical statement should not be construed as a general denial of the importance of rationalization or an attitude-to-counterarguments sequence. One furtheresult for the message-set contrast was a reduction in recall in the message-set condition. Message set simultaneously increased persuasion and decreased recall-a pattern of results in disagreement with Osterhouse and Brock's generalization from previously existing literature. Paradoxically, such results appear to contradict Zimbardo et al. 's original justification for the manipulation of distraction through message-set instructions. Our results suggest that message set is important because it leads to an increase in communication-favorable thoughts. It is thus possible that the previous studies which did not produce a decrement in recall were also studies which produced an increment in communicationfavorable thoughts. At this point the better part of wisdom might be to leave our results as they are and not attempt any further analyses. We, however, feel a bit frustrated being forced to speculate about the causal sequence giving rise to a pattern of correlated effects without recourse to any further tests. An adaptation of Blalock's (1964) procedure for testing causal models with correlation data can be used. This procedure compares specific models by statistically holding constant the postulated mediator or mediators between an initial variable and a final dependent variable. Thus a model which postulates that the effect of A on C is mediated solely by B predicts that the relationship between A and C would be within error variance of zero if B is held constant. Blalock uses either partial r's, or partial slopes, to hold variables constant.4 This technique can also be applied to relationships among four or more variables. Although the details become somewhat more complex, the basic logic remains the same. Thus a model which postulates a causal chain from A to B to C to D predicts that the relationship between A and D would be within error variance of zero when either B or C is held constant. Blalock's causal analysis procedure was originally designed for the analysis of data in a nonexperimental situation in which the "initial" variable is observed but not manipulated. Our immediate interest, of course, relates to the manipulation of distraction. In addition, since the multivariate analysis of variance program used for the standard analysis allows for the convenient covariation of additional variables, analysis of covariance is used to hold constant the mediators 4If bac.b = 0, rac.b = 0, since rac.b = (bacb) (bca B).

16 522 SOCIOMETRY postulated by the proposed causal model. Such a procedure is equivalent to the examination of partial slopes (cf. Scheffe, 1959).5 The proposed statistical procedure is thus the same as that followed by Osterhouse and Brock when they demonstrated that the effect of distraction on attitude change became nonsignificant when number of counterarguments was used as a covariate. However, Heise (1969) urges caution in the use of causal analysis in situations in which knowledge or theory does not allow for the specification of the temporal order of the variables. This appears to be the case here, particularly in view of Miller's previously described position that counterarguments are causally dependent upon attitude change. In Heise's later discussion of weakening the assumptions he does point out, however, that even without exact knowledge as to the causal priorities, causal analysis "... may be justified as a way of summarizing present knowledge in order to guide furtheresearch" (1969: 66).6 It is in that spirit that we offer the following causal analysis. In order to simplify reporting the covariance analyses we combined the two attitude-assessments by multiplying the rating scale by three and summing the product with the three semantic-differential ratings. When the covariance analyses were carried out independently on the two assessments, essentially the same results were obtained. (Tests for heterogeneity of regression were nonsignificant in every case.) For the combined assessments, the message-set versus message-only contrast gives an F of 3.55 (p <.04, one-tailed). When counterarguments are covaried, the attitude F drops from 3.55 to a nonsignificant Such results replicate Osterhouse and Brock's two studies, and are consistent with the mediational model originally proposed by Festinger and Maccoby, as well as the slightly more elaborate model we have proposed. Our causal model also includes communication-favorable thoughts as a mediator. When communication-favorable thoughts are used as a covariate, the attitude F drops from 3.55 to a nonsignificant.96. Specific precedent for the use of covariance to test causal models can be found in Cochran and Cox (1957:90). They discuss an example in which a chemical containing both fertilizer (nitrogen) and a fumigant simultaneously increased the yield of oats and reduced the number of eelworms. If the chemical still has an effect on the oats after number of eelworms is covaried out, Cochran and Cox maintain that the interpretation of the results is altered. The nitrogen component of the chemical was sufficien to increase yield independent of its effect on number of eelworms. 6Further discussion of the assumptions involved in causal analysis can be found in Heise's article.

17 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 523 These results, of course, are consistent with a mediational model which postulates an increase in the number of communication-favorable thoughts as a mediator of the facilitativeffect of message set on attitude change. What about the order of the two mediators, communication-favorable thoughts and counterarguments? Our proposal is that communication-favorable thoughts are temporally prior. The unadjusted F for message-set distraction on number of counterarguments is 9.02 (p <.01). After covarying communication-favorable thoughts the F becomes nonsignificant (F = 2.66, p <.11). These results are all consistent with the proposed causal model. One possible criticism of the present experiment is that we did not follow Brock's (1970) procedure of imposing a short three-minute time limit on the thought-listing task. The reason for such a time limit is the assumption that with more and more time the listed-thoughts may be increasingly response generated. If thelisted-thoughts are response generated, it is reasonable to distrusthe thoughts in the second half of the list more than the thoughts in the first half of the list. Accordingly, the two thought variables previously shown to be of importance, communication-favorable thoughts and counterarguments, were scored separately for the two halves of the list. Separate analyses for the two halves of the list revealed the same results as were obtained for the total list.7 So much for the facilitativeffect of message-set distraction upon attitude change. What about the hindering effect of task-set 7There were significantly more communication-favorable thoughts in the first then the second half of the list (F = 25.13, p<.01), and significantly more counterarguments in the second than the first half of the list (F = 22.69, p <.01). Otherwise, however, position in the list seems to make no difference. The message-set contrast on number of counterarguments is significant for both the first half of the list (F = 4.29, p <.04) and the second half of the list (F = 6.84, p <.01). Also the message set contrast does not have a significantly larger effect on the first than the second half of the list (F =.62). Further, the attitude F for the message-set contrast becomes nonsignificant when either the first half counterarguments or the second half counterarguments is used as a covariate (F = 1.55 p<.11, one-tailed, and F =.93, p<.17, one-tailed, respectively). The same picture emerges for communication-favorable thoughts. The message-set contrast on communication-favorable thoughts is significant for both the first half of the list (F = 11.04, p<.01) and the second half of the list (F = 16.82, p <.01). Also, the message-set contrast does not have a significantly larger effect on the second than the first half of the list (F =.14). Finally, the attitude F for the message-set contrast becomes nonsignificant when either the first half communication-favorable thoughts or the second half communication-favorable thoughts is used as a covariate (F = 1.03, p<.16, one-tailed, and F = 2.13, p <.08, one-tailed, respectively).

18 524 SOCIOMETRY distraction upon attitude change? The fact that the attitude change effect was paralleled by somewhat different effects than was the case for the message-set contrast suggests, consistent with our initial hunch, that different mediators are involved. The results indicated that the decreased attitude change in the task-set condition was paralleled by two effects: first, subjects reported exerting less effort listening to the communication in the task-set condition; and second, the communication was recalled less well in the task-set condition. There were no parallel effects for number of counterarguments or for communication-favorable thoughts. Consider first the results for effort. Subjects reported exerting less effort attending to the communication in the task-set condition than in the other two conditions, which do not differ from each other. Covarying effort reduced the attitude F for the combined assessment from 6.48 (p <.01) to 0.58 (n.s.). Our post hoc and tentative explanation for these results involves an application of cognitive consistency theory (e.g., Rosenberg, 1960). Consider the persuasive communication from the perspective of a subject who is primarily oriented toward completing the number task (i.e., a task-set subject). For such a subject, the communication is the distraction and, as such, interferes with the subject's goal of completing the number task. Thus from a consistency perspective, it is reasonable to suppose that in the task-set condition the communication and its advocated point of view should be negatively evaluated. The relevant cognitive band may be roughly as follows: "That distracting communication (-) interferes with (-) completion of the number task (+)." Thus, when the subjects report that they didn't exert a lot of effort listening to the communication, their responses may at least partially indicate that they did not like the communication because it interfered with their major role assignment. On the basis of this line of reasoning, one would not expect a negative evaluation of the communication in the message-set condition because in that condition the communication was not a distracting interference with completion of the major role assignment. In the message-set condition the task was the interference, and thus, according to this line of argument, should have been negatively evaluated. Unfortunately, task-evaluation data were not collected in the present study. The second and final effect for the task-set contrast was a decrease in recall in the task-set condition. Covarying recall did not make the attitude F nonsignificant (F = 4.42, p <.04), although there was a noticeable drop in the F from Such results do not support a

19 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 525 model which postulates recall as the only mediator of the task-set contrast, but, on the other hand, it is still possible that recall is one of the mediators of the task-set contrast. Historically, social psychologists have not agreed regarding the role of recall as a mediator of attitude change. As previously indicated, both Miller and Campbell (1959) and McGuire (1966) have argued for the mediational importance of memory processes. On the other hand, Greenwald (1967, 1968) has argued for the importance of thoughts, as opposed to recall, as the important mediator. Our data do not appear particularly helpful in resolving the controversy. Nonetheless, we are prepared to argue that recall is an important mediator. If recall is regarded as an index of what is in storage, then any emphasis upon the importance of thoughts will logically have to acknowledge the importance of recall. How can a thought process be relevanto a communication if there is nothing to process? Thus on purely rational grounds it makes no sense to rule out recall. This point can be illustrated by noting the sizeable difference in attitude between the control (or no-communication) condition and the experimental conditions. Since the control subjects had nothing in storage that could be cognitively processed, the lack of attitude change seems entirely reasonable. Historically, one of the puzzling things about the recall literature is that even when there are between-cell relationships between attitude and recall, the within-cell correlations are near zero. This was the case, for example, in studies by Miller and Campbell (1959) and Insko (1964) in which the major independent variable was time between opposing communications. Both of these studies found that the longer the time interval between opposing communications the greater the persuasive impact of the second communication and the greater the superiority in recall of the second communication; that is, time significantly increased both recency in persuasion and recency in recall. The within cell correlations, however, were nonsignificant and near zero. In the present study, the within-cell correlation between attitude and recall is also nonsignificant (r = -.02). And, also analogously to the earlier studies, the task-set contrast is significant for both recall and attitude. How can such puzzling results be explained? If effects are correlated between cells, why shouldn't they be correlated within cells? We suspect thatthe answerrelatesto the exceedingly flat slope relating recall and attitude change, together with the small within-cell range in recall. A relatively flat slope relating recall and attitude change indicates, in common sense terms, that it takes a relatively large change in recall before there is

20 526 SOCIOMETRY any associated change in attitude. If this is indeed the case, then it is quite reasonable that the within-cell correlation between recall and attitude change would be quite small given only the usual amount of within-cell variation in recall found in the typical college-subject population. On the other hand, if the independent variable is a very powerful one producing large variance in recall, the relationship between recall and attitude change appears. This seems to have been the case with the studies of time between opposing communications, and, in the case of the present study, with task-set distraction. It is also the case for the comparison of experimental and no-communication control conditions in this and in many other studies. One possible objection to this line of argument is that it is inconsistent with the message-set contrast. The message-set condition also produced a decrement in recall. In this instance, however, attitude change increased. It is clear from Table 1, however, that the decrement in recall produced by message set is not nearly as marked as the decrement produced by task set. In view of the flat recall-on-attitude-change regression, a considerable variation in recall is required before there is any associated variation in attitude. Thus, such results are not embarrassing to this line of argument. In general then, we are proposing that the negative effect of task set on attitude is due both to consistency-achieving devaluation of the communication and to a large decrement in recall. Such suggestions are offered in the spirit of guides for future research and obviously not as generalizations presently enjoying firm empirical support. Finally, it should be pointed out that there is a sense in which consistency or balance theory is relevant to both the facilitative and inhibiting effects of distraction upon attitude change. We have already pointed to the devaluation of the interferring communication under task set conditions as a possible explanation for the lesser amount of attitude change under those circumstances. As previously indicated, this is really a balance-achieving process. We have also argued for the importance of counterarguing as a partial explanation of the facilitativ effect of message set upon attitude change. A counterargument, of course, is a consistent cognitive band. In this case, it is a statement either that shorter summer vacations (-) would interfere with (-) certain desirable goals (+), or would facilitate (+) certain undesirable goals (-). In either case, application of the multiplicative rule results in a consistent band. It is also worth noting that from the perspective of Rosenberg's (1960) concept of attitude structure, it is to be suspected that counter-arguments may in some

21 EFFECTS OF DISTRACTION ON ATTITUDE CHANGE 527 instance rationalize existing attitudes. We believe that in many instances this indeed happens. However, in this particular situation, we regard it as more probable that the causal sequence goes in the other direction. REFERENCES Blalock, H. M., Jr Causal Interferences in Nonexperimental Research. Chapel Hill: University of North Carolina Press. Brock, T. C "Communication discrepancy and intent to persuade as determinants of counterargument production." Journal of Experimental Social Psychology 3 (July): Calder, B. J., C. A. Insko and B. Yandell 1974 "The relation of cognitive and memorial processes to persuasion in a simulated jury trial." Journal of Applied Social Psychology 4 (January): Cochran, W. G. and G. M. Cox 1957 Experimental Designs. (2nd ed.) New York: Wiley. Festinger, L. and N. Maccoby 1964 "On resistance to persuasive communications." Journal of Abnormal and Social Psychology 68 (April): Greenwald, A. G "An amended learning model of persuasion." Paper read at American Psychological Association, Washington, D. C "Cognitive learning, cognitive responses to persuasion, and attitude change." Pp in A. G. Greenwald, T. C. Brock, and T. M. Ostrom (Eds.), Psychological Foundations of Attitudes. New York: Academic Press. Haaland, G. A. and M. Venkatesan 1968 "Resistance to persuasive communications: An examination of the distraction hypothesis." Journal of Personality and Social Psychology 9 (June): Heise, D. R "Problems in path analysis and causal inference." Pp in E. F. Borgatta (ed.), Sociological Methodology. San Francisco: Jossey-Bass. Insko, C. A "Primacy versus recency in persuasion as a function of the timing of arguments and measures." Journal of Abnormal and Social Psychology 69 (October): McGuire, W. J "Attitudes and Opinions." Annual Review of Psychology 17: Miller, N "On measuring counterarguing." Paper presented at American Psychological Association, Washington, D. C.