Aerobic exercise and chocolate as means for reducing ... - Springer Link

Cognitive Therapy and Research, Vol. 17, No. 6, 1993

Aerobic Exercise and Chocolate as Means for Reducing Learned Helplessness Matisyohu Weisenberg, 1 Yael Gerby, and Mario MikuUncer Bar-llan University

This study tested the effects of 10 min of aerobic exercise, a chocolate snack, or guided imagery as a means of reducing the learned helplessness effects due to the experience of an unsolvable task. It was hypothesized that exposure to unsolvable tasks would lead to a higher level of anxiety, engagement in more task-irrelevant cognitions, and a poorer performance on a solvable test task. Intervention with either chocolate, 10 min of aerobic exercises, or guided imagery would reduce anxiety, reduce task irrelevant cognitions, and prevent performance decrement. Five groups of subjects (n = 100) were tested on a visual search task after experiencing an unsolvable task. Results indicated that the experience of the unsolvable task led to a higher level of anxiety arousal compared to a group that did not experience the unsolvable task. The intervention of either aerobic exercise, chocolate, or guided imagery led to a reduction in anxiety to the level of the control group that had not experienced an unsolvable task. Task-irrelevant cognitions were found to be higher in the classic nonintervention learned helplessness group and in the guided imagery group. The only group to suffer a performance decrement on the test task was the classic learned helplessness group without intervention. All three interventions were found to be equally effective in preventing performance decrement. Results are discussed in terms of an irrelevant defensive cognition/anxiety model as well as in terms of a controllability model KEY WORDS:learned helplessness; exercise; chocolate; anxiety reduction.

Performance deficits have been found in humans following prolonged exposure to unsolvable problems (e.g., Hiroto, 1974; Hiroto & Seligman, 1Address all correspondence to Professor Matisyohu Weisenberg, Bar-Ilan University, Department of Psychology, Ramat-Gan, Israel. 579

0147-5916/93/1200-0579507.00/0 © 1993Plenum Publishing Corporation

580

Weisenberg, Gerby, and Mikulincer

1975). In terms of learned helplessness (LH) theory (Abramson, Seligman, & Teasdale, 1978; Maier & Seligman, 1976), these deficits are due to a reduction in the expectancy of control. When people try to solve unsolvable problems, they may develop the expectation that outcomes are uncontrollable. If people transfer this expectation to subsequent controllable tasks, they put less effort into them and show performance deficits. The intervening role of the expectancy of control, however, is questionable. Research has shown that people have difficulty in learning that outcomes are independent of responses (Jenkins & Ward, 1965; Langer, 1975). Ford and Neale (1985) showed significant change in the perception of control following unsolvable problems. Moreover, Kuhl (1981) found performance deficits after unsolvable problems without the mediation of the expectancy of control. An alternative theory, the cognitive interference hypothesis, emphasizes the role of anxiety in explaining the performance effects of unsolvable problems (Coyne, Metalsky, & Lavelle, 1980; Lavelle, Metalsky, & Coyne, 1979; Mikulincer, 1989). This hypothesis, based on anxiety theory and research (Mandler, 1972; Mandler & Sarason, 1952; Sarason, 1975; Wine, 1971), states that the exposure to unsolvable problems results in anxiety and that anxiety-related cognitions impair test task performance. A feature analysis of the classic LH paradigm clearly reveals that the exposure to unsolvable problems fulfills the defining criteria of anxietyarousing situations: the unexpected interruption of an ongoing activity that blocks the ways to a goal and leaves the individual with no effective response to overcome the obstacles (Mandler, 1972, 1975). In the LH paradigm, the experimenter-induced failure is perceived as an unexpected interruption of a person's plans that blocks the attainment of a goal, in this case to solve the problems (Burger & Arkin, 1980). Moreover, the unsolvability of the problems leaves subjects with no means of overcoming failure. Several theories of anxiety emphasize the detrimental effects of anxiety on task performance. For example, Easterbrook (1959) claimed that anxiety reflects heightened arousal that interferes with the attention to environmental cues needed for task performance. Another early theory states that anxiety is a learned response which competes with task-relevant actions (Mandler & Sarason, 1952). Anxiety produces task-interference responses, such as "feelings of inadequacy, helplessness, heightened somatic reactions, anticipations of punishments or loss of status and esteem, and implicit attempts at leaving the task situation" (Mandler & Sarason, 1952, p. 166). The interference mechanism is explained in terms of the diversion of attention from task performance toward off-task cognitions (Geen, 1980; Hamilton, 1975; Sarason & Stoops, 1978). According to Sarason (1975),

Learned Helplessness, Exercise, and Chocolate

581

the anxious person divides attention between off-task cognitions (worry, self-doubt) and task cues, and the less anxious person focuses more fully on task-relevant stimuli. There is evidence that anxiety feelings and cognitions might contribute to performance deficits following unsolvable problems. Lavelle et al. (1979) found that characteristically anxious persons performed more poorly following failure than their less anxious counterparts. Mikulincer and Nizan (1988) found that failure increased the frequency of anxiety-related cognitions, which in turn impaired subsequent performance. Coyne et al. (1980) and Milulincer and Nizan (1988) found that manipulations designed to eliminate anxiety feelings and cognitions eliminated the performance effects of unsolvable problems. Among the techniques for reducing LH deficits are positive self-statements that influence mood (Kilpatrick-Tabak & Roth, 1978; Raps, Reinhard, & Seligman, 1980), instructions that reduce self-focus (Brockner, 1979), and pleasant imagery that leads to anxiety reduction (Coyne et al., 1980). For comparative purposes, only one of these techniques was chosen in the present study. The basic premise of this study was that it would be reasonable to expect that any preventive or therapeutic technique that can reduce anxiety could be an effective means of reducing these deficits. Coyne et al. (1980) followed this reasoning and demonstrated the effectiveness of guided imagery. Subjects were asked to imagine mountain scenery for 4 min. The imagery was presented as a physiological activity that improves problemsolving ability and helps subjects cope with tension. Compared to the classic learned helplessness subjects, no performance deficit was found following unsolvable problems that were followed by guided imagery. This study follows the preceding line of research and examines the effectiveness of other anxiety-reducing techniques for weakening performante deficits following unsolvable problems. Beyond guided imagery, the present study focuses on two other techniques that have been consistently shown to reduce anxiety: aerobic exercise and sugar ingestion. Research has shown that eating of a sugar snack or engaging in physical exercise, especially of the aerobic variety, can have stress- and anxiety-reducing effects (Hannaford & Harrell, 1988; Long & Haney, 1988; Thayer, 1987; Wurtman & Danbort, 1986). Both of these interventions have strong implications for the ease with which they can be used in a clinical setting. In this study, subjects were exposed to no-feedback or failure in four unsolvable concept formation problems. Failure subjects were further divided into four conditions according to the introduction of anxiety-reducing techniques after the unsolvable problems: (a) no anxiety-reducing technique, (b) guided imagery, (c) sugar ingestion, or (d) aerobic exercise. All subjects were subsequently tested on a letter cancellation task, and their

582


anxiety feelings and cognitions were assessed. Our predictions were as follows: 1. Subjects exposed to unsolvable problems without being provided with anxiety-reducing techniques will show more feelings of anxiety and anxiety-related cognitions and worse performance in the letter cancellation task than subjects in the no-feedback condition. 2. Subjects exposed to unsolvable problems who receive either aerobic exercises, sugar ingestion, or guided imagery will not significantly differ from no-feedback subjects in their reports of anxiety feelings and cognitions and task performance. 3. Subjects exposed to unsolvable problems who receive either aerobic exercises, sugar ingestion, or guided imagery will show less anxiety feelings and cognitions and better task performance than subjects exposed to unsolvable problems without anxiety-reducing techniques.

METHOD

Subjects One hundred (75 male and 25 female) volunteer subjects, ages 18 to 21, were assigned randomly to one of five groups, 20 in each group. To control for diurnal variations in reaction to sugar snacks (Spring, Mailer, Wurtman, Digman, & Conzolino, 1983), all subjects were asked to appear in the morning. All subjects were screened with a health questionnaire to eliminate those with problems of hypertension, heart disease, or diabetes.

Study Design Five independent groups were run in the study: (1) The learned helplessness group was exposed to an unsolvable task followed by a second solvable task. (2). The aerobic group was exposed to an unsolvable task followed by 10 min of aerobic exercises and then a second solvable task. (3). The chocolate group was exposed to an unsolvable task followed by a request to eat chocolate and then a second solvable task. (4) The guided imagery group was exposed to an unsolvable task followed by 4 rain of guided imagery using the procedure of Coyne et al. (1980) that had previously been found to reduce learned helplessness and then a second solv-


583

able task. (5) The no-feedback control group was exposed to the same tasks without the experience of failure.

Study Tasks and Measures The training task, which was designed to produce the failure manipulation, was taken from Mikulincer (1986). It consisted of four sets of cards that varied on four different dimensions----shape of card (square or triangle), letter (A or T), size of letter (large or small), type of line (continuous or broken). Subjects were told that they were to guess the concept that the experimenter chose. For learned helplessness conditions, subjects were told that they would be informed if they guessed correctly. The experimenter's responses were random, as no concept had been chosen. At the end of a series when the subject tried to guess the correct response, the subject was told that he/she failed. For the no-feedback control condition, no feedback was provided. The test task that followed the manipulation was taken from Mikulincer and Nizan (1988). It consisted of a visual search activity in which subjects were asked to search for two, four, or six letters among a series of letter matrices on three separate pages. Subjects were timed (1 min was allowed for each page) and scored for both the total number of letters scanned as well as for accuracy. The letters to be found were read by the experimenter and had to be remembered by the subject. Interference of thoughts that were not relevant to the task was assessed using the Cognitive Interference Questionnaire (CIQ) of Sarason, Sarason, Keefe, Hayes, and Shearin (1986). The CIQ consists of 21 items of which 10 relate to intrusive thoughts associated with task performance (e.g., concern about adequate task performance) and 11 to task-irrelevant thoughts (e.g., concern about family or friends). Factor analysis of the resuits of the present study supported the division of the scale into the two component parts suggested by Sarason et al. (1986). Subjects were asked to rate on a 5-point scale (1 = never, 5 = very often) the extent to which each thought occurred while they worked on the test task. A separate item on a 7-point scale asked for a global rating of the extent to which the person's mind wandered during the test task. Three separate scores were calculated: task-relevant thoughts, task-irrelevant thoughts, and extent of mind wandering. An analogue scale measure of anxiety was used as a means of assessing if the learned helplessness intervention did indeed produce anxiety. Subjects were asked to rate their anxiety on a scale from 0 to 100 as used by Weisenberg, Aviram, Wolf, and Raphaeli (1984). To check on the ma-

584


nipulation and yet not influence the outcomes by the act of measurement, only half the sample was randomly chosen to rate their level of anxiety immediately following the learned helplessness task. Following the manipulation to reduce learned helplessness, all subjects were asked to rate their anxiety.

Procedure Subjects were tested individually. Each subject was told that this was a study in learning composed of several tests: On the first test you will be asked to look at 10 cards similar to this (subject is shown a card). Each card has a combination of a shape and a letter made up of four dimensions: shape of the card (square or triangle), type of letter (A or T), size of letter (small or large), type of line (continuous or broken). This combination can be made up of one dimension, two dimensions, three dimensions or four dimensions. For example, I could choose the letter A with a square where the size or the type of line does not matter. Your task is to discover the concept that I chose by looking at each card and guessing whether the concept does or does not appear on that card. [For learned helplessness groups] I will tell you if you guessed correctly. At first your responses about the presence of the concept will be by guessing. However, by a process of elimination, and by learning from my reactions, you will be able to achieve greater and greater certainty. After 10 cards, I will let you tell me the concept that 1 chose, and I will tell you if you are correct or not. I will give you this test four times. Each time I will chose a different concept that you will have to discover.

For the learned helplessness groups the experimenter's response was five "correct" and five "incorrect" random responses. The subject's response at the end of a series was always called wrong. The no-feedback control subjects were asked to guess the concept. They were told that these responses were being gathered for another study, and no feedback was given during the trials. Following the training task, half of the subjects were randomly chosen and asked to rate their feelings of anxiety. No significant differences in any of the dependent variables were found between subjects asked to rate their anxiety twice and those not so asked. At this point the control group and the nonintervention learned helplessness group were asked to wait (approximately 10 min) while the next task was being prepared. The aerobic group was told, "We are investigating the question, 'Does exercise improve or decrease concentration?' Therefore you are being asked to perform a number of calisthenic exercises for 10 minutes according to my instructions." The following exercises were performed: 3 min of warmup consisting of stretching hands, bending back, and walking; 5 min of aerobic exercises that included jumps, fast walking, and running; 2 min of walking and loosening up of body muscles.


585

The chocolate group was told, "We are investigating the question, 'Does chocolate improve or decrease concentration?'" Each subject was asked to eat 50 g of chocolate. They were also asked to wait 10 min before beginning the next task. The guided imagery group, following Coyne et al. (1980), was told, "You are about to perform a physiological activity that helps people cope with stress, and apparently helps in problem solving. Try not to think of anything. Now I would like you to imagine a scene in which a mountain appears." Subjects were asked to do this for 4 rain and to wait an additional 6 min. The test task followed. Subjects were told that they were to be given a task that involved remembering letters. The letters they were to remember would appear on the sheets they would be given. The task would require them to scan each line of the page and place an X through the letter that appeared on the page. Subjects were informed that the task would be repeated three times, each time with a different set of letters to find. Subjects were allowed 60 s per page. Letters were randomly chosen. The first set used two letters (B, W), the second four letters (H, I, O, R), the third six letters (O, V, L, E, C, Z). Subjects were then asked to complete the CIQ and a rating of anxiety during the study. This was followed by a subject debriefing in which subjects were asked to vent their feelings. It was explained that their performances were fine and that it was not possible for anyone to solve the first task.

RESULTS

As no differences were obtained for gender, the data for the two sexes were combined.

Check on the Manipulation

This study postulated that experience with the unsolvable task would lead to an increase in anxiety and that the intervention strategies chosen would lead to a decrease in anxiety. A repeated-measures ANOVA of the anxiety ratings (following training and following the manipulation) yielded a significant group by time interaction,F(4, 48) = 4.63, p < .01. The data were analyzed further to clarify the interaction. An ANOVA analysis of anxiety ratings following the training task yielded a significant group result, F(4, 48) = 4.26, p < .01. Multiple comparisons by the Duncan New Multiple Range Test (Duncan, 1955) indicated that the control (no-feedback)

586


Table I. Means and Standard Deviations for Anxiety Ratings for Subjects Who Rated Anxiety Twice and for Subjects Who Gave Only One Rating by Experimental Group Control

Classic

Aerobic

Chocolate

Imagery

Anxiety rated twice Post training Mean SD

Post manipulation Mean SD

9.55 12.74

29.18 24.56

46.00 25.47

33.33 28.72

44.58 24.63

5.00 9.22

32.36 12.18

17.50 13.99

17.78 18.56

17.92 16.71

6.82 7.17

15.63 24.99

Anxiety rated once Post manipulation Mean SD

12.22 19.22

25.00 20.00

12.50 11.37

condition was significantly lower than the other four learned helplessness conditions. None of the other groups differed from each other (see Table

I). An ANOVA analysis of anxiety ratings following the intervention manipulation yielded significance for group, F(4, 95) = 5.08, p < .01. Multiple comparison by the Duncan indicated that the classic learned helplessness group was significantly higher than all the other groups, which did not differ from each other. Postanxiety ratings for subjects who rated anxiety levels twice did not differ significantly from their counterparts who rated anxiety only once (M = 18.11 and 14.43 for subjects who rated anxiety twice and once, respectively).

Cognitive Interference Although the MANOVA did not yield significant differences for the three CIQ measures, it was felt that it was justified to examine each measures separately as previous research had indicated selective effects (Miklincer, 1989; Mikulincer & Nizan, 1988). Univariate ANOVAs revealed no significant group differences for the task-relevant or for the overall wandering thoughts scores (see Table II). However, a significant group difference was obtained for task-irrelevant cognitions, F(4, 93) = 2.71, p < .05. Multiple comparisons indicated that the classic learned helplessness and

587

Learned Helplessness, Exercise, and Chocolate Table lI. Means and Standard Deviations for Cognitive Interference Scores by Experimental Group Cognitive interference measure Task-relevant Mean SD

Task-irelevant Mean SD

Wandering thoughts Mean SD

Experimental group Control

Classic

Aerobic

Chocolate

Imagery

2.11 0.56

2.41 0.60

2.25 0.64

2.24 0.53

2.11 0.56

1.37 0.63

1.93 1.06

1.36 0.46

1.25 0.21

1.67 0.95

2.15 1.30

2.30 0.86

2.75 1.77

2.73 1.32

2.63 1.06

the guided imagery intervention groups scored higher than the other three groups which did not differ from each other.

Test Task Performance A MANOVA analysis of the test task performance for the amount completed did not yield any group differences (see Table III). However, a MANOVA analysis indicated that the groups significantly differed on the accuracy scores, F(12, 246) = 1.98, p < .05. Further analyses by ANOVA showed that significant differences were found in the four-letter, F(4, 95) = 2.73, p < .05, and in the six-letter, F(4, 95) = 4.68, p < .01, conditions. Multiple comparisons indicated that the classic learned helplessness condition yielded a significantly lowered performance than the other groups. The three intervention groups did not differ from each other or from the no-feedback control group.

DISCUSSION This study postulated that exposure to an unsolvable task would increase anxiety and lead to a higher level of irrelevant cognitions that would interfere with subsequent performance on the test task. The data showed that exposure to the unsolvable task increased anxiety compared to a nofeedback control group that did not experience the unsolvable task. In turn, the manipulations of either 10 rain of aerobic exercises, eating chocolate,

588

Weisenberg, Gerby, and Mikulineer Table III. M e a n s a n d Standard Deviations for A m o u n t C o m p l e t e d a n d P e r c e n t a g e Accuracy Scores on the Test Task Number of letters to search

Experimental group Control

Classic

Aerobic

Chocolate

Imagery

N u m b e r of letters completed Two letters Mean SD

428.80 202.49

352.00 105.36

361.60 130.95

414.40 160.66

364.80 168.17

F o u r letters Mean SD

246.40 112.82

281.60 166.30

262.40 143.33

230.40 84.72

257.60 151.33

Six letters Mean SD

232.00 165.09

212.80 145.08

209.60 146.60

209.60 115.36

172.80 65.99

Percentage accuracy o f l e t t e r s completed Two letters Mean SD

67.90 20.82

69.28 18.60

76.64 21.73

73.49 16.47

74.35 20.57

Four letters Mean SD

71.32 16.67

55.85 20.71

74.37 23.65

71.24 18.21

71.85 20.46

Six letters Mean SD

67.64 20.56

45.07 14.66

61.54 22.13

66.70 18.73

65.06 19.39

or guided imagery led to a reduction in anxiety compared to a classic learned helplessness group without an intervention. In terms of interfering cognitions, of the three measures, the irrelevant cognition scores were lower for the aerobic and for the chocolate groups as compared to the classic learned helplessness group and the guided imagery group. The effect on the test task was seen in the greater accuracy of the three intervention groups for the four-and for the six-letter tasks but not for the two-letter task. No differences were obtained for the amount of the test task completed, implying that the manipulation affected attentional more than motivational factors. There is thus some support for the hypotheses of this study. Overall, the data are consistent with the model of Kuhl (1981) and with the work of Mikulincer and Nizan (1988) and Mikulincer (1989). According to this approach, learned helplessness induced by failure at an unsolvable problem leads to anxiety arousal and a state in which the person


589

focuses more on him/herself rather than on the task. The anxiety and selffocus, as seen by the increase in anxiety ratings and by the greater number of irrelevant cognitions, leads to a poorer performance on the subsequent test task. The significant difference for irrelevant cognitions is consistent with other studies (Mikulincer, 1989; Mikulincer, Kedem, & Zilkha-Segal, 1989; Mikulincer & Nizan, 1988) and could be interpreted as typical for anxiety reactions that lead to self-preoccupation and thus interference with cognitive, task-oriented, problem-solving activity (Kuhl, 1981; Wine, 1971). However, it is important to note that there was also a greater number of irrelevant cognitions for the guided imagery group in addition to the classic learned helplessness group. This would support the notion that not all irrelevant cognitions lead to a performance decrement. The guided imagery instructions almost by definition lead to irrelevant cognitions. Although no specific data were collected to support the premise, it is plausible to assume that these irrelevant cognitions are conductive to relaxation rather than to anxiety arousal. Similar, Mikulincer (1989) reported that only defensive, rather than all, off-task cognitions were associated with task performance decrement. The performance decrement obtained in this study was for accuracy in the more difficult four- and six-letter categories but not for the easier two-letter task nor for the total number of letters scanned. The type of performance deficit obtained has not been consistent across studies. Mikulincer (1989) found performance differences mainly in terms of accuracy, whereas Mikulincer et al. (1989) obtained differences in both measures of performance. In the present study, there are a number of factors that could account for the differences being found on the accuracy measure only. The specific instructions emphasized that the task was being timed and asked subjects "to work as fast as you can." There was no emphasis on accuracy as being more important than speed. Although there were significant differences obtained for anxiety, the overall levels of aroused anxiety were not very high (46 out of 100 for the highest). The 10-min break also could have helped dissipate some of this anxiety as well. It is possible, therefore, that only the more complex tasks brought out the differences in performance (cf. Bond, 1982; Cottrell, Rittle, & Wack, 1967). Only 10 min of aerobic exercises or eating a chocolate snack were as effective as guided imagery and can be added to other techniques that have been demonstrated as effective for the reduction of learned helplessness phenomena (e.g., Brockner, 1979; Kilpatrick-Tabac & Roth, 1978; Raps et al., 1980). It is likely that these effects are mediated by anxiety reduction and by the consequent reduction of threatening, intervening, irrelevant thoughts that are aroused by the learned helplessness manipulation.

590


This study, however, cannot rule out the possible influence of controllability as an additional mediator of these effects. It is possible that the intervention contributed to a sense that some aspect of the situation was under the subject's control. This would be similar to the results of Long and Haney (1988), who demonstrated that relaxation and physical exercise not only reduced anxiety, but also increased the subject's sense of self-efficacy. It is also not possible to completely rule out the effects of distraction or expectancy that could be responsible for the positive effects of the various manipulations. However, these alternatives also can be anxiety-reducers in and of themselves (Weisenberg, 1989). Additional study would be desirable to test these alternatives for learned helplessness deficits. The present study was designed only to demonstrate the basic influence of exercise or eating on learned helplessness phenomena. Further research would be worthwhile to test differences for different types and amounts of food. Is the effect limited to sweet snacks, or is any kind of food equally effective? In addition, just as Thayer (1987) has demonstrated differences between a sugar snack and 10 min of exercise over a 2-hour period, so too it might be worthwhile to examine the effects of chocolate or exercise for long-term effects.

REFERENCES Abramson, L. Y., Seligman, M. E. P., & Teasdale, J. (1978). Learned helplessness in humans: Critique and reformulation. Journal of Abnormal Psychology, 87, 49-74. Bond, C. F. (1982). Social facilitation: A self presentational view. Journal of Personality and Social Psychology, 42, 1042-1050. Brockner, J. (1979). Self-esteem, self consciousness, and task performance: Replications, extensions, and possible explanations. Journal of Personality and Social Psychology, 37, 447-461. Burger, J. M., & Arkin, R. M. (1980). Prediction, control, and learned helplessness. Journal of Personality and Social Psychology, 38, 482-491. Cottrell, N. B., Rittle, R. H., & Wack, D. L. (1967). Presence of an audience and list type (competitional or noncompetitional) as joint determinants of performance in paired-associates learning. Joto71al of Personalio,, 35, 425-434. Coyne, J. C., Metalsky, G. L., & Lavelle, T. L. (1980). L e a r n e d helplessness experimenter-induced failure and its alleviation with attention redeployment. Journal of Abnormal Psychology, 89, 350-357. Duncan, D. B. (1955). Multiple range and multiple F tests. Biometrics, 11, 1-42. Easterbrook, J. A. (1959). The effect of emotion on cue utilization and the organization of behavior. Psychological Review, 66, 183-201. Ford, C. E., & Neale, J. M. (1985). Learned helplessness and judgments of control. Journal of Personality and Social Psychology, 49, 1330-1336. Geen, R. G. (1980). Test anxiety and cue utilization. In I. G. Sarason (Ed.), Test anxiety: Theory, research, and applications (pp. 43-61). Hillsdale, NJ: Erlbaum. Hamilton, V. (1975). Socialization anxiety and information processing: A capacity model of anxiety-induced performance deficits. In I. G. Sarason, & C. D. Spielberger (Eds.), Stress and Anxiety (Vol. 2, pp. 45-68). New York: Wiley.


591

Hannaford, C. P., & Harrell, E. H. (1988). Psychophysiological effects of a running program on depression and anxiety in a psychiatric population. The Psychological Record, 38, 37-48. Hiroto, D. S. (1974). Locus of control and learned helplessness. Journal of Experimental Psychology, 102, 187-193. Hiroto, D. S., & Seligman, M. E. P. (1975). Generality of learned helplessness in man. Journal of Personality and Social Psychology, 31, 311-327. Jenkins, H. M., & Ward, W. C. (1965). Judgment of contingency between responses and outcomes. Psychological Monographs: General and Applied, 79, 1-17. Kilpatrick-Tabak, B., & Roth, S. (1978). An attempt to reverse performance deficits associated with depression and experimentally induced helplessness. Journal of Abnormal Psychology, 87, 109-120. Kuhl, J. (1981). Motivational and functional helplessness: The moderating effect of state vs. action orientation. Journal of Personality and Social Psychology, 40, 155-170. Langer, E. (1975). The illusion of control. Journal of Personality and Social Psychology, 32, 311-328. Lavelle, T. L., Metalsky, G. I., & Coyne, J. C. (1979). Learned helplessness, test anxiety, and acknowledgment of contingencies. Journal of Abnormal Psychology, 88, 381-387. Long, B. C., & Haney, C. J. (1988). Coping strategies for working women: Aerobic exercise and relaxation interventions. Behavior Therapy, 19, 75-83. Maier, S. F., & Seligman, M. E. P. (1976). Learned helplessness: Theory and evidence. Journal of Expelimental Psychology: General, 105, 3-46. Mandler, G. (1972). Helplessness: Theory and research in anxiety. In C. D. Spielberger (Ed.), Anxiety: Current trends in theory and research (Vol. 2, pp. 359-374). New York: Academic Press. Mandler, G. (1975). Mind and emotion. New York: Wiley. Mandler, G., & Sarason, S. B. (1952). A study of anxiety and learning. Journal of Abnormal and Social Psychology, 47, 166-173. Mikulincer, M. (1986). Attributional processes in the learned helplessness paradigm: The behavioral effects of globality attribution. Journal of Personality and Social Psychology, 51, 1248-1256. Mikulincer, M. (1989). Cognitive interference and learned helplessness: The effects of off-task cognitions on performance following unsolvable problems. Journal of Personality and Social Psychology, 57, 129-135. Mikulincer, M., Kedem, P., & Zilkha-Segal, H. (1989). Learned helplessness, reactance, and cue utilization. Journal of Research in Personality, 23, 235-247. Mikulincer, M., & Nizan, B. (1988). Causal attribution, cognitive interference, and the generation of learned helplessness. Journal of Personality and Social Psychology, 55, 470-478. Raps, C. S., Reinhard, K. E., & Seligman, M. E. P. (1980). Reversal of cognitive and affective deficits associated with depression and learned helplessness by mood elevation in patients. Journal of Abnormal Psychology, 89, 342-349. Sarason, I. G. (1975). Anxiety and self preoccupation. In I. G. Sarason & C. D. Spielberger (Eds.), So'ess and anxiety Vol. 2, pp. 27-44). Washington, DC: Hemisphere. Sarason, I. G., Sarason, B. R., Keefe, D. E., Hayes, B. E., & Shearin, E. N. (1986). Cognitive interference: Situational determinants and trait like characteristics. Journal of Personality and Social Psychology, 51, 215-226. Sarason, I. G., & Stoops, R. (1978). Test anxiety and the passage of time. Journal of Consulting and Clinical Psychology, 46, 102-109. Spring, B., Mailer, O., Wurtman, J., Digman, C., & Conzolino, L. (1983). Effects of protein and carbohydrate meals on mood and performance. Jottrnal of Psychiatric Research, 17, 155-167. Thayer, R. E. (1987). Energy, tiredness, and tension effects of a sugar snack versus moderate exercise. Journal of Personality and Social Psychology, 52, 119-125. Weisenberg, M. (1989). Cognitive aspects of pain. In P. D. Wall & R. Melzack (Eds.), Textbook ofpahl (2nd ed., pp. 231-241). Edinburgh: Churcfhill Livingstone.

592


Weisenberg, M., Aviram, O., Wolf, Y., & Raphaeli, N. (1984). Relevant and irrelevant anxiety in the reaction to pain. Pain, 20, 371-383. Wine, J. (1971). Test anxiety and direction of attention. Psychological Bulletin, 76, 92-104. Wurtman, J. J., & Danbort, M. (1986). Managing your mind and mood through food. New York: Harper and Row.