Bchel. R<,\ & Therop,. Vol 19. pp 193 to 200. 1981 C0X-7967 81iO30193.08502.00~0 Prmtcd ,n Great Br~tam All nphts reserved Copynpht 0 1981 Pergamon Press Ltd

SELF-CONTROL OF SMOKING-II EFFECTS OF CUE SALIENCE AND SOURCE OF DELAY IMPOSITION

ON THE EFFECTIVENESS OF TRAINING UNDER INCREASING DELAY*

ALEXANDER NEWMAN? and ROBIN BLCK~M Department of Psychology, Hunter College of the City University of New York,

695 Park Avenue, NY 10021. U.S.A.

(Receiwd 27 December 1978)

Summary-Imposed increasing delay of cigarette puffs has been shown to facilitate smoking inhibition. Hypothetical mechanisms involved (frustration extinction or rehearsal of coping re- sponses) imply that increased temptation cue salience and decreased degree of external control in increasing delay training should facilitate smoking inhibition. After three pre-test delay tolerance trials, all subjects were cued to pace their smoking in an increasing sequence of delay. During treatment the cigarette temptation cues were either visible or hidden. Delays were either self- imposed but cued by the experimenter or the delays were physically imposed by the experimenter. Post-test consisted of three delay tolerance trials. Pre-test to post-test improvement was signifi- cantly facilitated by cue salience and reduced external control. No significant interaction effects were obtained. Cue salience significantly reduced the self-reported aversiveness and GSRs during self-control trials. Implications for treatment were advanced.

Smoking reduction is often considered a self-control problem because it usually requires a self-initiated decrease in the probability of a response (i.e. smoking) resulting in the forfeit of immediate positive reinforcement (e.g. physical stimulation of nicotine, anxiety inhibition) in favor of delayed negative reinforcement (e.g. avoiding cancer, cardiovascu- lar and other disorders). Generally, self-control training programs involve the active acquisition of new controlling responses such as narrowing stimulus control (Nolan, 1968; Roberts, 1969), self-monitoring (McFall, 1970; McFall and Hammen, 1971), self- reinforcement (Gutman and Marston, 1967) positive self-punishment (Axelrod et al., 1974). coverant control (Rutner, 1967: Keutzer, 1968; Lawson and May, 1970; Gordon and Sacks, 1971; Tooley and Pratt, 1967), thought stopping (Wisocki and Rooney, 1971), covert sensitization (Cautela, 1971; Wagner and Bragg, 1970) and so forth. The require- ment for acquisition of new coping responses suggests that the response repertoires of smokers, alcoholics, drug addicts etc., do not contain effective controlling responses. Alternatively, effective controlling responses may already be in the persons’ repertoires, but not adequately rehearsed. Accordingly, self-control training should involve confron- tation with actual self-control situations rather than the acquisition of new responses.

Skinner (1948) suggested a self-control training regimen that involved simply exposing subjects to increasing delays of reward intervals. Newman and Kanfer (1975) tested Skinner’s notion in young children. In a training phase, when the subject made the correct response in a discrimination learning task a small candy reward was delivered after 0, 10, 20, 40 or 60 set fixed delay; or it was given after 60 set for the first block of four trials, and the delay interval was decreased every four trials; or it was given immedi- ately in the first block of four trials, and every subsequent trial block was gradually increased. In a subsequent test the increasing delay group demonstrated resistance to temptation significantly superior to that of the decreasing and fixed delay groups. No significant differences among the fixed delay groups and between the fixed and decreasing

* This research was supported by a grant from the Research Foundation of the City University of New York. t To whom all requests for reprints should be addressed.

193

194 ALEXANDER NEWMAN and ROBIN BLOOM

delay groups were found, indicating that the superiority of the increasing group was not due merely to variability of delay intervals.

Newman and Bloom (1977) later demonstrated that merely exposing smokers to a sequence of increasing waiting periods facilitates smoking inhibition (i.e. the amount of time subjects could wait in the presence of a lit cigarette before taking a puff). Two explanations of the superiority of increasing delay training were advanced. In the increas- ing delay condition, subjects were first given immediate reward. When the delay was introduced, the delay interval was aversive because it was effectively a time out from positive reinforcement (e.g. Leitenberg, 1965). It is likely that subjects attempted to reduce the aversiveness by emitting various coping (controlling) responses. When the reward was delivered, it reinforced not only the correct response but also the coping response which more immediately preceded the reward. As the delay increased, the frequency of coping responses also increased. It is hypothesized that these subjects in the self-control situation employed these coping responses to reduce the aversiveness of delay, and, as a result, demonstrated resistance to temptation superior to that of subjects in the decreasing or random delay groups.

The alternative explanation posits that the aversiveness of a delay of reward interval is due to a conditioned emotional response, called frustration (Amsel, 1967). Recent evi- dence has indicated that conditioned frustration is similar to conditioned fear in the sense that both can motivate, as well as disrupt, other behavior (e.g. McAllister and McAllister, 1971). Thus, delay of reward early in training has been found to produce larger galvanic skin responses than those produced by immediate reward (Ware and Terrell, 1961). In general, graded exposure to aversive stimuli results in fear reduction (cf. Herzberg, 1941; Levine, 1942; Schubot, 1966). Therefore, if delay of reward is aversive. exposing subjects to gradually increasing delays of reward should extinguish the aversive effects of delay, thereby enhancing the potency of the ultimate negative consequence (i.e. physiological disorders) and facilitate self-control.

While these two proposed mechanisms are not necessarily mutually exclusive and may interact in a cybernetic fashion (i.e. coping responses reduces frustration which in turn reinforces the coping response), variables important to the design of effective therapy programs may be deduced and empirically assessed.

The present investigation is concerned with the assessment of two such variables: cue salience and degree of external control. Specifically, if frustration is to be extinguished it may be necessary to elicit frustration in the context of an extinction procedure (e.g. counter-conditioning, graded exposure, implosion, etc.). Increasing delay training should therefore be maximally effective when training proceeds under high temptation cue salience. Frustration would then be elicited and would be subject to extinction through graded exposure. Accordingly, temptation salience in increasing delay training should facilitate smoking inhibition. Similarly, if temptation cue salience increases aversiveness of delay, responses which effectively reduce aversiveness may be elicited and by success- ive approximation, shape these coping responses and thereby permit direct confrontation to temptation cues.

A second variable deduced from these hypothetical mechanisms is the effect of the degree of external control in training. Frustration theory posits that self-imposed delay is more frustrating than externally imposed delay. A training regimen to extinguish frustra- tion is less likely to generalize to the self-control problem response when training includes external controls then when external controls are minimized. Similarly, if self- control involves an active mechanism of emitting coping responses to frustration rather than the passive mechanism of frustration extinction, training in self-control should include active rehearsal of these coping responses under stimulus configurations that closely approximate the problem situation. Since most self-control problems involve self-imposed delay, coping responses rehearsed under these conditions are likely to be more easily generalized than those responses rehearsed during externally-imposed delay. Therefore, increasing delay training should be more effective in reducing smoking when the delays are self-imposed than when they are experimenter-imposed because the

Self-control of smoking-11 195

demands in the training situation would more closely approximate those required of the subject in testing. The present study assesses the contribution of these variables on the effectiveness of increased delay training.

Specifically, the purpose of the present study is to test the hypothesis that training under high salience of the tempting stimuli (i.e. a lit cigarette physically in front of the subject and within reach) will result in a greater smoking inhibition than will low salience (i.e. cigarette hidden from view of subject). It is predicted that increasing sequences of self-imposed delay of reward will facilitate smoking reduction more dramatically than will experimenter-imposed delay. In addition, the relative reduction of aversiveness, measured by self-report and physiological indices, will be assessed.

METHOD

Subjects

The subjects were 40 male and 40 female undergraduate student volunteers at Hunter College recruited from undergraduate psychology classes. They received no course credit for participation. All subjects had smoked a minimum of one and a half packs a day for over a year.

Apparatus and materials

The experimenter monitored the latency of smoking using a hand-held stop watch. Galvanic Skin Responses (GSR) were recorded using Marietta Self-balancing GSR Model 75A-12-1OOR. The lit cigarette was placed on or in an 8 in. diameter. Glaro cigarette urn with flip-top cover, model 44.

Procedure

The experimenter, a female graduate student, recruited subjects for this experiment by an announcement in several introductory psychology classes. She asked for smokers to volunteer for an experiment primarily concerned with physiological changes during smoking. Volunteers chose an individual appointment for participation. On the appli- cation form they wrote their name, telephone number, how many cigarettes they smoked a day, and how long they had been smoking. If they met the criterion of 30 cigarettes a day for over a year they were told that they qualified for the study. They were asked to abstain from cigarettes for 1 hr before their appointment.

When the subjects appeared for their individual appointments they were informed that the study would simply involve having non-painful and non-dangerous electrodes placed on the second and fourth fingers of their non-dominant hands. They were assured that there would be no shock or risk of physical danger from the apparatus. They were further instructed that they would be cued when to take a puff from their cigarettes so that the recordings could be accurate. Each subject was brought individually to the experimental room, was shown the equipment, and was given an informed consent form to sign.

Pre-test

Electrodes were placed on the index and fourth finger. The subjects were then asked to light a cigarette and put it in the ashtray. After the cigarette was placed in the ashtray directly in front of the subject, they were told that initial physiological recordings were being taken. The subjects were told to take a puff of the cigarette whenever they wanted to but to wait as long as possible before taking the puff so that the experimenter could get as much physiological data as possible. After the first puff, the subjects were asked to wait as long as possible until the next. This was repeated for a total of three such self-control trials during which the experimenter recorded the subjects’ latency and GSR recordings.

196 ALEXANDER NEWMAN and ROBIN BLOOM

Treatment

The subjects were told that the next phase of the experiment was concerned with those physiological changes which occur when people try to reduce their cigarette smoking, and that this study was not interested in inducing subjects to stop smoking. They were informed that a lit cigarette would be placed in an ashtray and that the experimenter would periodically request them to take a puff of the cigarette. They were further instructed to take only one puff of the cigarette in order for the experimenter to obtain clear physiological readings and then to place the cigarette back in the ashtray. All subjects were first told to take a puff immediately. Delay then increased 10 set every trial. Thus, after the thirtieth trial, subjects were asked to take a puff every 240 sec. A fresh cigarette was lit immediately following the subjects’ last puff on the cigarette if it had burned about 6.5%.

The experimental manipulation was cigarette (reward) cue salience and experimenter vs self-imposed delay combined factorially. In the salient condition, the cigarette was placed on the cigarette urn directly in front and within reach of the subject during each waiting period. In the hidden condition, the cigarette was placed inside the urn during the waiting period.

In the experimenter-imposed delay condition, the experimenter picked up the cigarette and gave it to the subjects at the end of each waiting period. After one puff. the experi- menter took the cigarette from the subjects and placed it on (for salient) or in (for hidden) the cigarette urn. Thus, the experimenter had direct control of the cigarette throughout training, and the delays were therefore imposed. The subjects in this condition were not able to smoke between trials.

In the self-imposed delay condition, the subjects were told that after a certain amount of time had elapsed the experimenter would signal them to take a puff of the cigarette. The subjects in this condition were told that since the cigarette would always be in the ashtray, they could take a puff before the experimenter signaled if they wished. The subject was informed that the physiological recordings would be better if they would wait until the experimenter did signal, but if they took a puff before the signal, the physiologi- cal reactions would still be accurate and quite adequate. No subject in this condition did take a puff before being cued. Thus, the experimental design is a 2 (salient vs hidden cues) x 2 (experimenter vs self-imposed delay) factorial design.

Post-test

The post-test involved the same three trial pre-test delay tolerance procedure and recordings of GSR and latency (i.e. amount of time the subject could wait in front of a lit cigarette before taking a puff). Subjects were then given a post-experimental question- naire that included a rating scale assessing perceived effectiveness of the procedure to facilitate smoking reduction and aversiveness of the waiting periods in pre-test and post-test.

RESULTS

Although subjects were assigned to treatment conditions randomly, an analysis of variance was performed to assess the possibility of sampling bias with respect to subjects’ smoking histories. There were no significant differences between groups with respect to either number of cigarettes smoked every day, or number of years of smoking.

This experiment was primarily concerned with testing the immediate effects on smok- ing inhibition of one self-control training procedure which was either experimenter- imposed or self-imposed and in which temptation cues were salient or hidden. The major dependent variable was the amount of time a subject resisted taking a puff in pre-test and post-test. The delay tolerance latencies are presented in Fig. 1.

To examine the overall change from pre-treatment to post-treatment, imposition (2) x salience (2) x phase (2) x trials (3) analysis of variance was performed on the amount of time subjects waited before taking a puff. A significant salience main effect was

Self-control of smoking-11 197

-----soIf-Saliult ----Exparimmtar- sallont

-Salt-Hlddrn -----Exporhsnkr- Hiddon

300

275

PN Post PhOXO

Fig. 1. Mean changes in tolerances to duration of smoking inhibition as a function of self vs experimenter-imposed increasing delay under cigarette cue salient vs hidden.

obtained, F( 1,76) = 26.03, P < 0.001. Subjects improved significantly across phases, F(1,76) = 131.29. P c 0.001. The predicted significant phase x source of imposition interaction effect, F(1, 76) = 4.96, P < 0.05, and phase x cue salience effect, F(1,76) = 29.51, P < 0.001, were found. F-test of simple effects indicated that groups did not differ in pre-test, but did in post-test. F(1, 76) = 7.10, P < 0.01 and 8.24, P < 0.01, respectively. All other interaction effects were nonsignificant.

To obtain a more sensitive method of change, one that takes into account each subject’s initial response level and permits intercorrelations among the dependent vari- ables. residual change scores were used after testing that required assumptions were met (Benjamin, 1967; Tucker er al., 1966). Residual change scores consisted of the difference between the obtained post-test score and a post-test score predicted on the basis of linear regression from the appropriate pre-test score. This analysis assumes homogeneity of means and variances for pre-test scores and a significant correlation between pre-test and post-test scores. In order to test the assumptions for a residual change score analysis, one way of variance of waiting time at pre-test was performed and indicated no significant effect. In addition, Bartlett’s test for homogeneity of variance revealed no significant differences among the variances of the four groups (Corrected X2 = 2.31, P > O.iO). Finally, a significant correlation between pre-test and post-test was obtained, r(80) = +0.31, P < 0.05.

An analysis of variance on the residual change scores indicated that self-imposed delay induced longer waiting than did experimenter-imposed delay F(1,76) = 4.28, P < 0.05. In addition, training under cue salience induced significantly longer waiting in post-test than did training with cues hidden, F(L76) = 37.61. P < 0.001. Finally, there was no significant interaction between source of imposition and cue salience.

Analysis of variance of amplitude GSR in log conductance, indicated a significant phase x salience interaction effect, F(l, 76) = 3.45, P < 0.05. F-test simple effect indi- cated no significant differences in pre-test and a significant decline in GSR to post-test under cue salient condition. F(1,76) = 8.59, P c 0.01; and no significant difference in GSR in post-test in cue hidden condition.

An analysis of variance of subjects’ ratings of aversiveness of waiting periods in pre-test indicated no significant differences between groups. In post-test, however, cue salient

198 ALEXANDER NEWMAN and ROBIN BLOOM

groups rated the waiting periods significantly less aversive than did cue hidden groups. F(1.76) = 7.64, P c 0.01. Subjects in the self-imposed delay condition did not rate the aversiveness of the waiting periods significantly different than did subjects in the experimenter-imposed condition. Finally, cue salience was reportedly helpful in eliminating smoking, F(1,76) = 24.91, P < 0.001. Source of imposition of delay was not rated as a significant variabie. Cue salient x source of imposition interaction was not reliable.

DISCUSSION

Cue salience increased tolerance to delay of smoking and reduced self-reported aversive- ness of delay and GSRs in post-test. Self-imposed delay in training increased smoking inhibition but did not effect change in GSR. Thus, cue salience and self-imposed delays are variables that improve resistance-to-temptation in an experimental manipulation. While the experimental demonstration of the contribution of these variables are consis- tent with the proposed mechanisms, they do not necessarily demonstrate the discrimin- ant validity of these proposed mechanisms rather than the other mechanisms. The present study is further limited in that it was an analogue employing one session focused on short-term effects on self-control in smokers who did not express a desire to stop smoking, and did not investigate the content of specific coping responses spontaneously emitted. In addition, although the experimenter was uninformed of the hypothesis tested and the expected direction of differences, possibility of experimenter bias confounding cannot be ruled out. This study, however, is suggestive of subseuqent research ultimately to be tested in the clinic.

For example, one premise of contemporary behavior therapy is that generalization from treatment to outcome will be facilitated by similarity of training and testing situ- ations. If this premise is empirically validated treatment programs should not occur in the absence of the tempting stimulus. Many contemporary treatment programs of addic- tive problems, whether they be drug addiction. alcoholism. smoking or weight reduction etc., proceed in the absence of the tempting stimulus, apparently based on the old adage, “Get thee behind me, Satan” (Mischel, 1961). Thus, an alcoholic will frequently be incarcerated and, in the absence of the physical stimulus of alcohol, will be given verbal therapy focusing primarily on intention statements which become highly reinforced. Generalizability between these treatment programs and the actual self-control problems clearly is minimal (e.g. Bernstein, 1969; Mausner, 1969). This approach appears to rest on weak empirical support based on studies with young children which demonstrated the debilitating effects of facing real rewards during a delay period (Mischel and Ebbeson, 1970; Mischel er al., 1972; Schack and Massari. 1973). These results generally show that young children cannot delay gratification for long when confronted with the contingent reward for which they are waiting and that delay of grati~cation appears to be dimin- ished by attention to rewards during the delay period (Mischel. 1974). Although increas- ing the salience of reward may be more aversive during treatment (and therefore perhaps increase rate of defection), more dramatic improvements might be expected when reward cues are salient during delay of reward intervals than when they are hidden. This of course. remains an empirical question.

The findings of this study suggest that generalization to actual self-control tasks may be best effected by maximizing the presence of these stimulus elements in training, usually found in testing. Therefore, self-control treatment programs may be more effec- tive if it provides rehearsal in the execution of self-control in the presence of the tempting stimuli rather than exertion of external controls such as physical restraints, punishment, group pressure, etc. Programs such as Alcoholics Anonymous maintain external control (i.e. peer pressure) and meet with such success as long as the person is a member of the group. When external pressure is removed. the self-control problem generally reappears. Indeed many, if not most. treatment programs require the client simply to make the intention statement to execute self-controi and to be willing to submit to the externally controlled conditioning regimen (e.g. aversive conditioning). Our suggestion that treat- ment programs include rehearsal in self-control rests on scant empirical support. Com-

Self-control of smoking--II 199

parative studies aimed at ascertaining the relative efficacy of a self-control technique and external control technique utilizing identical controlling responses are lacking except in the specific areas of systematic desensitization (e.g. Arkowitz, 1969; Kahn and Baker, 1968) and reinforcement contingencies (e.g. Bolstad and Johnson, 1972; Glynn, 1970). The question of whether a self-presented stimulus has the same effects as the identical stimulus presented by the experimenter was initially raised by Skinner: “The ultimate question of aversive self-stimulation is whether a practice of this sort shows the effect which would be generated by the same stimulation arranged by others”. (Skinner, 1953, p. 239). Since these recommendations suggest a wide departure from current modes of treatment, extensive research with long-term follow-up in both the laboratory and clinic is required to determine the validity of these recommendations.

Acknowledgement-The authors wish to express their sincere appreciation to Michele Gagan for her comments on an earlier version of the manuscript.

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