Currently, there is a large and increasing literature suggesting the positive effects of meditation, its applications to health care, psychotherapy, and education. When one reads the literature, there are only two studies reported which suggest possible negative effects (1,2). Unfortunately, most journals do not report negative effects because of lack of statistical significance due to small sample size. From a clinical perspective, however, negative effects are quite important. This article describes a study done at SRI to determine what, if any, are the negative effects of Transcendental Meditation.
Our investigation came about as a result of reader reaction to an article that the author published in Psychology Today (3) in 1974. The article summarized an experiment conducted at SRI to determine whether people who adopted the practice of Transcendental Meditation (TM) were a self-selected population or whether a relatively disinterested random sample of volunteers could realize the benefits claimed to accrue to practitioners. In the article, the author briefly mentioned that the SRI findings suggested TM may not be a suitable practice for everyone, and he cautioned that it might even be harmful for some. After the article was published, the author began to receive unsolicited letters, telephone calls, and some visits from people complaining about adverse effects from TM.1)
In the research, we used a relatively neutral population of 60 volunteer SRI employees; half were randomly assigned to learn TM and the other half were assigned to learn and practice one of three control conditions.2) The TM group received the standard training at a local chapter of the Students International Meditation Society (SIMS), the parent organization of TM. After training, they were instructed to meditate twice daily for 15 to 20 minutes for the next three months. Two groups of control subjects received mock »meditation« training and subsequently practiced sitting quietly twice daily. One group was instructed to relax as best they could. The other group was given a »mock« mantra and was told to mentally repeat the phrase »I am a witness only« during their meditation periods. In contrast to these two »active« control groups, the subjects in a third passive control group did not change their lifestyle in any way. They simply reported for the baseline and the subsequent psychological and physiological tests that were given to all subjects.
Well before the three-month period of daily practice was over, we began to receive complaints during weekly meetings about physical or mental distress (headaches, insomnia, anxiety, gastrointestinal upset, etc.) from both the TM and active control subjects. The problems the TM subjects experienced were interpreted by the SIMS organization as being caused by »unstressing«--a phenomenon claimed to be a natural consequence of the initial stages of TM. We could not explain the problems reported by control subjects but assumed that they were transient and need not overly concern us. We were wrong, at least with respect to a few of the subjects. Two of the controls were advised by their physicians to terminate their participation in the experiment because of the reoccurrence of previously quiescent medical problems. Three of the TM subjects quit because of medical or other problems.
Because the percentage of dropouts in the TM group was low and because subjects in the control groups also experienced problems, we believed that uncontrolled variables probably accounted for the adverse effects. Also, in the light of the glowing reports of the effects of TM appearing in the literature (4), the author simply mentioned these unexpected results in the Psychology Today article and cautioned that further research might be needed.
Unlike other investigators (5,6), we found no differences in EEG, alpha frequency, heart rate, blood pressure, peripheral blood pulse volume, respiration rate, skin temperature, or personality measures between the TM and the combined control groups. The absence of differences between the TM and control groups, however, may have been due to the short (i.e., three-month) period of practice of our TM subjects. Interestingly, the TM subjects showed significantly more Sleep Stage 1 than control subjects. TM subjects tended to vacillate between light sleep and wakefulness more than controls (7)--results that have since been corroborated by others (8,9).
During the period between 1972 and 1974, when the Psychology Today article appeared, other factors developed that kept the question of possible adverse effects alive for this investigator. Conversations with colleagues at national meetings where the SRI experimental results were presented indicated that they also had noted adverse effects in some people, especially in subjects from a psychiatric population. We also compared dropout rates, which varied from 35 to 70% over a year. The question of why people dropped out was intriguing, but the press of other demands precluded the author’s pursuing this question.
The totally unexpected response to the few brief lines about possible adverse effects that he had included in his article rekindled the author’s interest. The people who wrote, called, or visited him were everyday folks--housewives, students, tradesmen, professionals--and their distress was real. Many reported adverse effects that continued even though they had stopped meditating. A few reported that they felt addicted to TM. That is, they said that quitting had exacerbated their symptoms, and they had started again to keep from feeling worse. Some of these people had been in meditation for years before their problems arose, and some had quit without their problems disappearing. Therefore, this researcher believed that there were some important unknowns regarding the possible effects of TM that merited further investigation.
He reexamined the results of a survey SRI had sent to every twentieth person on the SIMS mailing list in 1971 (approximately 40,000 individuals were on the mailing list then).3) Approximately 47% of the 1900 people surveyed responded to the survey, which included two instruments developed by the author that were intended for use in the SRI experiment. One was a self-concept word list (Descriptive Personality List) and the other was a checklist of physical and behavioral symptoms (Physical and Behavioral Inventory). The SIMS sample was used to validate the tests before they were used at SRI. Both tests proved to be valid in that each discriminated significantly between dropouts and those practicing TM for six months or less, as well as those practicing TM for 18 months or more. The tests also discriminated between the latter two TM groups.
Relevant to the present discussion is the symptom checklist, which consisted of three parts. Part I requested information about the subject’s TM history. Included were such items as when the subject was instructed, how long he or she had been practicing, how regularly the subject had practiced, and whether he or she was still practicing. Part II was a list of behavioral symptoms, culled from the literature on TM, that practitioners most frequently reported had changed for the better (see Fig. 1).
PART II. BEHAVIORAL INVENTORY
Fig. Symptom check list.
The subject was asked to indicate in Column 1 whether the category was a problem before he or she started TM and to check Columns 2, 3, 4, or 5 to indicate the extent and kind of change (positive or negative) noted since starting TM. Part III mirrored Part II, except that symptoms related to physical health were used.
The responses of all members of three subgroups of the SIMS sample were analyzed. The subgroups consisted of 121 people who had discontinued the practice (average time in TM was 7.4 months), 156 »novice« meditators (those who had been practicing for three to six months; average was 4.2 months), and 78 »experienced« meditators (those who had been practicing TM for 18 months or more; average was 22.7 months).
Initially, we compared dropouts with experienced meditators because we expected that considerably more dropouts would claim adverse effects than experienced meditators. Surprisingly, and totally unexpectedly, the reverse was true. Dropouts reported fewer complaints than experienced meditators, and to a statistically significant extent.4) To evaluate the reliability of this unexpected finding, we also analyzed the data for the novice meditators. Novice meditators fell between dropouts and experienced meditators in terms of the number of complaints.
Table 1 summarizes these data and presents data from a similar analysis of identical questionnaires returned by a group of novice (three to six months TM) and experienced (18+ months) meditators who were being trained to become teachers of TM.5) The latter data were examined to test the generalizability of the SIMS data to another TM population. Approximately 71% of this sample of 832 returned the survey questionnaires.
Although the original expectations were that the number of adverse effects reported would be negatively correlated with the length of time in meditation and that dropouts would report the greatest number of adverse effects, Table 1 shows that the opposite was the case. The number and severity of complaints were positively related to duration of meditation. That is, people who had been meditating for the longest period of time reported the most adverse effects. Of considerable interest is the finding that the specific adverse effects reported were remarkably consistent between groups and formed a pattern suggestive of people who had become anxious, confused, frustrated, depressed, and/or withdrawn (or more so) since starting TM.
Several other aspects of the table are of interest. In the SIMS sample, none of the adverse effects were reported to have increased by 51% or more by at least 5% of those who had dropped out of TM, and only one item (anxiety) was so reported by the naive meditators. In contrast, at least 5% of the experienced meditators reported that ten of the 12 adverse effects listed had increased by 51% or more since they started practicing TM. A similar pattern was seen for the teacher trainees. The naive meditators in the teacher trainee group reported that five of the 12 adverse effects had increased by 51% or more since starting TM, whereas those who had practiced TM for 18 months or longer identified the same ten adverse effects reported by the experienced SIMS meditators as having increased by 51% or more.6)
These data suggest that the longer a person stays in TM and the more committed a person becomes to TM as a way of life (as indicated by the teacher trainee group), the greater the likelihood that he or she will experience adverse effects. This contrasts sharply with the promotional statements promulgated widely by the SIMS, IMS, WPEC 7), and related TM organizations that TM is a simple, innocuous procedure.
Two hypotheses, alone or in combination, may be advanced to explain these data. The first is that the practice of meditation makes a person more aware of his or her problems and/or more willing to report them. A comparison of the two groups of naive meditators from the SIMS and the teacher trainee samples, however, does not support this hypothesis. Although both groups had been meditating for approximately the same length of time, the SIMS group reported that only one adverse effect had increased by 51% or more, whereas the trainee group reported that five adverse effects had increased by this percentage. This finding suggests that differences between people in their commitment to TM as a way of life may be a more critical variable. More of the naive meditators who had decided to become teachers of TM reported becoming depressed, frustrated, impulsive, and/or as experiencing greater physical and mental tension and suspiciousness since starting TM than did the naive meditators in the SIMS random sample. Of considerable interest is the finding that this trend was magnified the longer that individuals practiced TM. The experienced meditators in both samples reported considerably more adverse effects than the dropouts or naive meditators in either sample.
The second hypothesis is that the adverse effects reported are a manifestation of »unstressing,« a term used by the SIMS organization to describe an initial, transient process whereby the problem areas in one’s life are solved or »normalized.« it This could, presumably, include experiencing all the adverse effects listed in Table 1, and perhaps others. If the adverse effects we found were due to unstressing, however, it would seem reasonable to expect that those who had practiced TM for 18 months or more would experience fewer problems in their lives and therefore less unstressing than naive meditators. Our results were the exact opposite. The experienced meditators (and not the naive ones) reported the most adverse effects.
It could be argued, however, that the longer an individual practices TM the more willing he or she becomes to allow problems to surface and that this could account for the greater number of adverse effects reported by experienced meditators. Should this be the case, one might legitimately question how long it takes before unstressing results in the normalization of the problem areas in one’s life. In an attempt to follow up on this question, we reanalyzed the responses of individuals in our SIMS and teacher trainee samples that had been practicing TM for three years or more (average, 46.7 months). Table 2 shows that these very long-term meditators continued to report the same type of adverse effects. Consistent with differences previously noted between the SIMS and teacher trainee groups, the seasoned meditators in the trainee group reported that all 12 of the symptoms listed had increased in severity, where the SIMS group identified only seven as becoming more of a problem since they started TM. Also, in every case but one (physical and mental tension), a greater percentage of the seasoned trainees reported a worsening of symptoms than did the seasoned SIMS group. Accordingly, we may conclude from these data that if adverse effects are due to unstressing, unstressing may continue for at least four years and that adverse effects are more poignantly experienced by teacher trainees than by those less committed to the TM way of life. These data do not support the contention that unstressing (if unstressing accounts for our data) is an initial, transient process.
The number of subjects in each sample who contributed the data used in constructing Tables 1 and 2 was determined by tabulating the number of individuals in each of the subgroups that identified one or more adverse effects as having increased by at least 51% after starting TM. The results are shown in Table 3. As Table 3 shows, the percentage of TM practitioners (including dropouts) reporting one or more adverse effects included a sizable portion of the sample (range was 19.8 to 48.6%).
Table 1. Percentage of TM Dropouts and Meditators Reporting Adverse Effects*
*Only symptoms for which at least 5% of the subjects of one or more subgroups reported an increase of 51% or more are tabulated.
Table 2. Percentage of Long-Term Meditators Reporting Adverse Effects*
*Only symptoms for which at least 5% of the subjects reported an adverse change of 51% or more are tabulated.
**A decrease of 51% or more for these items was reported.
Table 3. Percentage of Practitioners that Reported that One or More Adverse Effects Had Increased 51% or More Since Starting TM
Two alternative hypotheses are suggested that may account for the consistent increase in adverse effects reported by long-term practitioners. The first is that the practice of meditation per se engenders adverse effects and/or exacerbates prior symptoms. A corollary is that the longer one practices TM, the more exacerbated his symptoms become.
The second hypothesis is that dropouts and those who continue the practice of TM may differ in some fundamental way(s) prior to learning TM. In the SIMS sample the dropouts reported significantly fewer symptoms as »problems« in the Physical and Behavioral Inventory before starting TM than did either the naive or experienced meditators (see Column 1, Fig. 1). Naive meditators also reported significantly fewer problems than the experienced meditators. Since the experienced meditators were asked to recall problems that may have existed two years earlier (average time in TM for the experienced meditators was 22.7 months), however, an argument could be that they had poorer recall and therefore erred in claiming more problems than the other two groups. This argument may be valid for the experienced meditators as compared with dropouts; the latter had meditated 7.4 months, on the average, before discontinuing the practice whereas the naive meditators had been meditating an average of only 4.2 months at the time of the survey. Dropouts had to recall events that occurred almost twice as long ago as did the naive meditators. Yet they claimed significantly fewer problems before starting TM. Thus, the hypothesis that recall errors accounted for the differences in the number of problems claimed by the different groups before they started TM is not supported. A more likely hypothesis is that fundamental differences existed between dropouts and those that continued the practice of TM. The latter appeared to have more problems before starting TM than the former.8)
Further evidence of fundamental differences between dropouts and those that stayed in TM comes from an analysis of the Descriptive Personality List which measured the individual’s self-concept. As mentioned earlier the Descriptive Personality List was also circulated to SRI subjects and survey respondents. Analysis of this test indicated that both the SRI subjects and the SIMS sample that dropped out of TM admitted to more negative traits (were realistically more self-critical?) than did those that stayed in TM. Within the SIMS sample the dropouts claimed significantly more negative traits than the naive or the experienced meditators. The difference between the SRI dropouts and those that continued in TM was of borderline significance (p<.10). Of considerable interest, however, is the finding that this difference was evident in the SRI group during baseline (i.e., pretraining) tests as well as during tests given three and 12 months after training. These findings support the supposition that the differences between the dropouts and naive and experienced SIMS meditators in the number of negative traits claimed also may have been evident before these groups had started meditating.
Irrespective of which of these hypotheses, if either, is correct, our data raise serious doubts about the innocuous nature of TM. In fact, they suggest that TM may be hazardous to the mental health of a sizable proportion of the people who take up TM.
The writer has formulated a tentative theory to explain the occurrence of adverse effects associated with TM. The theory suggests that there are two major interacting variables operating. The first is physical and the second is mental. The physical variable relates to the sitting posture assumed by the meditator and the loss of support (which may be experienced as frightening) that invariably occurs if the individual enters a sleep pattern during the meditational period (7, 8, 9). The person’s head may fall forward and be snapped to the upright position forcefully, or he may catch himself falling from his chair. Both of these events may be experienced as an acute anxiety episode, and the associated physiological state may be adversely conditioned to the practice of TM, per se. Thus, the frequent (most likely, aperiodic) occurrence of this sequence of events over a period of months or years of practice could lead to meditation, per se, becoming the occasion for the arousal of emotional disturbance. Such disturbance could generalize to thoughts about meditation during nonmeditational periods of the day so that the person could experience an increase in his or her overall level of emotional upset--variously interpreted as increased anxiety, depression, confusion, etc.--since starting the practice of TM.
The mental variable relates to the possible release of repressed material during the meditation period, especially during the period when the individual hovers between light sleep and wakefulness. While the individual is thinking his mantra, other thoughts typically displace the mantra. Some of these thoughts may represent previously repressed material which are sufficiently disturbing to abruptly shift the level of arousal from a low level (i.e., from a level of relaxation and/or light sleep) to a high level (i.e., fully awake). If the individual returns to thinking his mantra when this occurs, a self-regulated desensitization of the disturbing thought(s) could occur. If, however, the emotional disturbance occasioned by the release of the previously repressed material is too great, or if he does not return to thinking the mantra but perseveres in thinking the aroused anxiety-provoking thoughts, he may experience a high level of emotional disturbance or even loss of control. Such loss of control by TM practitioners has been witnessed by neutral observers invited as guests to rounding sessions (17).
A curious question remains: Why do people who experience adverse effects continue the practice? At this stage, we can only speculate about the reasons. One may be that the benefits received outweigh the negative effects. It is difficult, however, to imagine a benefit that would outweigh the pervasive anxiety and depression reported by some of the correspondents. Another reason may be that, like all well-learned habits, TM is difficult to extinguish. Many people have written that they continue meditating because they feel worse if they do not. Some have even compared meditation to a drug addiction and complain about feeling trapped--not wishing to continue but unable to stop.
Particularly curious is the desire of very long-term meditators who have experienced or are experiencing adverse effects to become teachers, that is, to pass on the practice to others. It may be that such individuals have, in fact, had a number of positive experiences and have been told that their current complaints will eventually disappear. The strong social reinforcement and encouragement offered by practitioners who do not experience adverse effects and the TM organizational representatives are undoubtedly difficult to set aside.
We hope that the data reported here will not discourage people from taking up TM or clinicians from using TM as an adjunct to traditional therapeutic interventions. It is clearly of benefit to many people. In our survey samples approximately 52 to 64% of the subjects who continued the practice did not list a single adverse effect as defined in our study (i.e., a change of 51% or more for the worse). Nevertheless, adverse effects do occur in a sizable percentage of those who take up the practice. Furthermore, the probability of occurrence of adverse effects is higher among psychiatric populations (10, 12, 13). Accordingly, clinicians who incorporate TM and possible other relaxation or meditational techniques into their practice should be vigilant about the possible occurrence of adverse effects and be prepared to deal with them. Experience indicates that frequent, if not daily, monitoring of psychiatric patients trained to meditate is advisable (12, 13).
A final word appears justified regarding SIMS promotional efforts. SIMS advertises that TM results in beneficial effects for anyone who takes up the practice and learns to perform it »correctly.« Our data raise serious doubts about the validity of this position. It is hoped that SIMS will publicly recognize that problems may be engendered by meditation and so instruct potential initiates as well as offer guidelines to both the general public and the psychotherapeutic profession for their amelioration. Most needed in this field are reliable instruments and considerably more rigorous, well-controlled studies to determine who may profit from meditation and who may not.
1. SIMS, the parent organization of TM, circulated a »rebuttal« to the article to all its teachers in the United States without giving the author an opportunity to respond. A disillusioned teacher informed the author that teachers were provided with »standard answers« to the points raised in the article, especially those concerning the possibility of adverse effects.
2. The initiation fee was covered by research project funds. The controls were given an equivalent amount for their participation in the experiment.
3. The mailing of the questionnaires was undertaken by the SIMS headquarters in Los Angeles. The sample was instructed to return the completed forms to SRI. Stamped, self-addressed envelopes were provided.
4. All references to statistical significance in this paper are at the 0.05 level of significance or better. In all cases two-tailed t tests for independent groups were used.
5. This group also included a number of teachers. The number is indeterminant from the survey data, but they would most likely be included within the group of experienced meditators.
6. Since this paper was written, similar data were analyzed for individuals who had been meditating for between six and 12 months in both the SIMS teacher trainee groups. The SIMS sample (N 92) reported increased antisocial behavior (8.7%), anxiety (7.6%), and decreased restfulness of sleep (6.5%). The teacher trainee sample (N 152) reported increased anxiety (5.9%) and depression (5.3%).
7. WPEC is the acronym for World Plan Executive Council.
8. Our experience has suggested that among the naive meditators, approximately 50% drop out before the end of the first year. Thus, this group included both potential dropouts and potential experienced meditators. It would be interesting to determine whether those who eventually dropped out had fewer presenting problems than those who remained in TM long enough to fit our criterion of »experienced« meditators.
1. French, A. T., Snid, A. C., and Ingails, E. Transcendental Meditation, altered reality testing and behavioral change: A case report. Journal of Nervous and Mental Diseases, 1975, 161, 55-58.
2. Lazarus, A. A. Psychiatric problems precipitated by Transcendental Meditation. Psychological Reports, 1976, 39, 601-602.
3. Otis, L. The facts on Transcendental Meditation: Part III. If well-integrated but anxious, try TM. Psychology Today, 45-46 (April, 1974).
4. Bloomfield, H. H., Cain, M. P., Jaffee, D. T., and Kory, R. B. TM: discovering inner energy and overcoming stress. New York: Dell Publishing Co., 1975. (A favorable summary of many of the positive claims and research results.)
5. Wallace, R. K., Benson, H., and Wilson, A. F. A wakeful hypometabolic state. American Journal of Physiology, 1971, 221, 795-799.
6. Hjelle, L. A. Transcendental Meditation and psychological health. Perception and Motor Skills, 1974, 39, 623-628.
7. Otis, L. TM and Sleep. Paper presented at the American Psychological Association Convention, New Orleans, 1974.
8. Younger, J., Adriance, W., and Berger, R. J. Sleep during Transcendental Meditation. Perception and Motor Skills, 1975, 46, 953-954.
9. Pagano, R. P., Rose, R. M., Stiver, R. M., and Warrenburg, S. Sleep during Transcendental Meditation. Science, 1976, 191, 308-31 0.
10. Benson, H. The relaxation response. New York: William Morrow & Co., Inc., 1975.
11. Benson, H. Systemic hypertension and the relaxation response. New England Journal of Medicine, 1978, 296, 11 52.1155.
12. Carrington, P. Freedom in meditation. Garden City, New York: Anchor Press/Doubleday, 1977.
13. Glueck, B. C. and Stroebel, C. F. Biofeedback and meditation in the treatment of psychiatric illness. Comprehensive Psychiatry, 1975, 16, 303-321.
14. Gopi Krisna. Kundalini. The evolutionary energy in man. Boulder, Colorado: Shanbhala Publications, 1971.
15. Luthe, W. Autogenic Standard Therapy: Non-Indications, Contraindications and Relative Contraindications. Basic Training Course in Autogenic Therapy, Hospital St.-Jean-de-Dieu. Montreal, Canada: 1974. See also W. Luthe and J. H. Schultz. Autogenic therapy. Vol. II: Medical Applications. New York: Grune & Stratton, 1969.
16. Wesch, J. E. Clinical Comments Section. Newsletter of the Biofeedback Society, 1977, 5(3), July.
17. Benson, H., Personal communication.
Reprinted with permission from Deane H. Shapiro and Roger N. Walsh, editors, Meditation: Classic and Contemporary Perspectives (New York: Aldine Publishing Co.), copyright 1984 by Deane H. Shapiro and Roger N. Walsh.