Psychological defence mechanisms in patients with pain

161

Pain, 40 (1990) 161-170 Elsevier

PAIN 01529

Psychological defence mechanisms in patients with pain Elisabeth Tauschke a, Harold Merskey avband Edward Helmes b uDep.ofResearch, London Psychiatric Hospital, London, Ont. {Canada), and

’ Dept. of Psychiatry, University of Western Ontario,

Landon, Ont. (Canada) (Received

25 April 1989, revision received 28 July 1989, accepted

17 August

1989)

There is a long standing position that pain, and especially chronic pain, may arise from psychological mechanisms of SUrn~ defenee. We have compared a group of chronic pain patients with a sample of psychiatric patients attending for reasons other than pain. The pain group had less evidence of poor care in childhood (measured by the Parental Bonding Instrument) and tended to use more mature psychological defence mechanisms (assessed with the Defense Mechanisms Inventory), compared with the other group. The pain group also had fewer current psychiatric diagnoses but more evidence of anxiety and depression on the Hospital Anxiety and Depression Scale. We conclude that in general the patients with chronic pain had more normal childhoods and more mature defences than the psychiatric control group. They showed an increase in the diagnosis of depression, attributable to reactive factors. In the sample of patients with pain the majority of the psycholo~cal change cannot be attributed to the operation of primitive psychological defences. Key words: Chronic

pain;

Psychological

mechanisms;

Defence

Psychiatric diagnosis and psychological explanations The relationship between psychological factors and pain is a continuing matter of interest. Freud saw pain as the result of a conversion neurosis, serving as a compromise between the fulfilling of a forbidden wish and its punishment [15]. He offered both a diagnosis (conversion hysteria) and a dynamic explanation of its production. The literature has regularly followed this pattern. Most authors have attempted first to define the psychiatric diagnoses with which pain is associated and then to identify the mental mechanisms which may generate pain as a bodily symptom [30]. The

Correspondence to: H. Merskey, D.M., Department of Research, London Psychiatric Hospital, 850 Highbury Avenue, P.O. Box 2532, London, Ont. N6A 4H1, Canada. 03043959/90/$03.50

0 1990 Elsevier Science Publishers

majority have described pain as a conversion neurosis, a hypochondriacal reaction or a form of depression [28,23,40]. One of the first systematic studies on a series of patients came from Engel [12,13] who diagnosed most of his cases as hysteria or h~~hond~asis. He described characteristic features in patients suffering chronic pain: a history of suffering, defeat, neglect and abuse in their childhood that resulted in the prominence of guilt and a strong aggressive drive that is not fulfilled; the experience of pain taking the place of emotion, a location of pain determined by unconscious identification with a love object; and the development of pain upon loss or threatened loss. Engel’s portrayal of the ‘pain-prone’ patient had a strong influence on subsequent research. Merskey [25] found that resentment was much commoner in patients with pain than in those without. The communicative function of pain was

B.V. (Biomedical

Division)

162

also evident in patients with lower intelhgence and education, but Spear [44] found no increased association with either hostility or covert aggression in patients with pain. Thus the description of patients by Engel was only confirmed in part. There is very little other work which is methodologically satisfactory and which would support Engel’s concept [e.g.. see 4,481. The second prominent diagnosis in research on pain and psychological factors is depression [40]. Of all psychological patterns, depression seems to have the strongest association with pain, yet the nature of a causal relationship between chronic pain and depression remains unsettled. Again methodological difficulties prevent definite conclusions. Pain is the most common complaint in medicine [3] and apart from substance abuse, depression and anxiety are the most common psychiatric disorders in the general population [31]. Their prevalence contributes to the strong link found between them and pain and makes the matter difficult to disentangle. In the theories of Freud and Engel, for both depression and pain, the concept of aggression directed inwards is a key psychodynamic explanation. However, Von Knorring [.50] pointed out that systematic studies on this theory have been contradictory for depression. It is more so for pain. Hypotheses on the relationship between pain and depression vary from regarding pain as an equivalent of a depressive disorder j6] or as a masked depression 121,221, to proposing that they are psycholo~cally independent but share common physiological or biological mechanisms [52]. Some claim the same psychological factors for the development of pain and depression [51,52]. When a physical explanation for pain has not been found, a psychological cause is often proposed for the pain without supporting psychological evidence [27]. However, research which focussed on the effects of a chronic painful illness on the life and personality of the patient suggested that depression was mainly a consequence of the painful condition [45,55]. Benjamin et al. [4] found that distinguis~ng between painful conditions caused by physical lesions and others did not seem to show whether psychological factors, especially

depression, were primary or secondary to pain. 1n their sample, patients without a physical lesion showed significantly lower ratings for severity 01 psychological problems than patients with physical lesions and the authors concluded that pain patients cannot be divided into a simple dichotomy of those with physical or mental illness. Two recent studies investigating children suffering from migraine found a negative and stressful impact of a painful condition on the personality and mood of the children [ 1.91. The family background has been said to affect the relationship between depression and pain. As we have noted above, Engel [13] suggested similar psychodynamic mechanisms for pain and depression. His description of the family background of pain patients resembles that of many depressed patients. But although it is widely held that the family plays an important role in the health of its members, the exact relationship with pain is far from being resolved. Pilowsky et al. [38] showed that childho~~d hospitalization could contribute both to depressive illness and to intractable pain in adults. Preschool admission to hospital had occurred more often in depressed patients than in a rheumatology group. Later childhood admission was more common in :I pain clinic group. There have been two extensive reviews on the association between pain and families - the families of origin as well as the family in which the patient is currently living [36,48]. Although Payne and Norfleet find some hints supporting Engel’s theory, they state that empirical evidence is lacking. Turk and his colleagues in their more recent review came to the conclusion that for almost all related questions there has been much interesting hypothesizing but very little empirical study and support. Many of the difficulties arose from the problem that all studies were retrospective, and the transformation of a correlation into a causal relationship has been mostly a matter of interpretation. Further, few studies made adequate allowance, or indeed any allowance, for the influence of selection in patients with pain f26J. Crook and Tunks [8] provide a notable exception in the examination of patients from pain clinics and the community, but adequate control studies

163

of families are few in number or slight in quantity. Merskey et al. [29] found that pain patients did not seem to have significantly different childhood experiences from patients in general practice, whether their pain was mostly physical in origin or whether there was no obvious physical explanation of the pain experience. However, general practice populations are themselves selected and there is some modest evidence that patients with pain and no lesions have more difficult parents than patients with lesions [28].

Defence mechanisms

Defence mechanisms are unconscious mechanisms that are supposed to protect against external and internal stressors [14]. They might be a help in clarifying some of the confusions between psycholo~cal factors, especially childhood experience and depression, and the experience of pain. For example, it might be postulated that pain associated with lesions will manifest different defence mechanisms from pain without lesions. In a related study, we found that the choice of defences is influenced by the relationship between parents and children [46]. It seems that good parental care increases the use of more mature defences. We found that maternal care has the strongest influence in reducing defences of aggression and hostility whereas paternal care supports defences that produce socially acceptable behaviour. So far as we know, there have been two reports to meetings [10,22] and only two published articles investigating defence mechanisms in pain patients [34,35]. All these studies have used the Defense Mechanisms Inventory (DMI) [17,19]. The DMI is a paper and pencil test that measures the relative strength of 5 defensive clusters. The test comprises 10 stories describing conflict situations, including issues relating to conflicts around authority, competition, ind~endence and sex. The subjects are asked to state their most likely actual behaviour, what they would most like to do, their thoughts and their feelings in response to each circumstance which the stories describe. Thus 4 responses are required with respect to each story. For each of

these responses, the subjects have a choice of 5 answers in accordance with the 5 defensive scales. These are defined by Gleser and Ihilevich as follows: Turning Against the Self (TAS), Turning Against the Object (TAO, including identification with the aggressor and displacement), PROjection (PRO), REVersal (REV, including negation, denial, reaction formation and repression), and PRINcipalization (PRIN, including intellectualization, isolation and rationalization). The test has an unusual feature in that the description of one type of behaviour, wish, thought or feeling, reduces the score for other such categories that can be attributed to the subject. In other words it is an ipsative measure: the total score for any set of responses remains the same. Only the relative strength of defence mechanisms within individuals can be measured with accuracy [2]. The DMI usually takes 30-45 min to complete. Each answer in each modality (what the subject would be likely to do, what he would prefer to do, what thoughts or feelings he would have) has a score of 0,l or 2. The sum of the 4 scores is added for each defence. The theoretical range of scores for any defence summed through the 10 questions is from 0 to 80. The reliability and validity of the test have been investigated in many studies [19]_ Internal consistency estimates range from 0.57 to 0.83 for the separate scores, apart from a reliability of 0.21 for Turning Against the Self in a homogeneous set of normal females. Test-retest reliability in studies by 3 authors on 4 samples averaged 0.62-0.82 for the 5 scales separately [19]. In studies of validity, independent raters have found satisfactory correspondence for items keyed to Turning Against the Self, Reversal and Principalization (more than 60% agreement) [5,19]. Additional validation includes a correspondence between observed responses to threats and the DMI categories, correspondence between the concept and the results of a principal components analysis, weak but significant empirical relationships with perceptual styles, some relationships with hemispheric localization, and a relationship between Turning Against Others and Projection on the one hand, and norepinephrine production after surgical operations.

164

Studies in pain patients Passchier and his colleagues examined 59 patients suffering from migraine, 32 patients suffering from tension headache and 26 control subjects. The participants were recruited by advertisements and were investigated with a test battery incIuding a non-validated Dutch version of the Defense Mechanisms Inventory ]17]. The results showed no significant differences between the groups with regard to inadequacy. debilitating anxiety, facilitating anxiety, impulsiveness, obsessive-compulsive behaviour and defence mechanisms. Migraine patients and tension headache patients each showed elevated achievement motivation, while rigidity was mainly present in the latter group. In their second study, however, Passchier et al. [34] found that their students with migraine scored higher on Turning Against the Self and lower on Projection and Turning Against the Object than their control group of students without migraine. Mendelson [24] found Reversal to be used relatively more often in his pain patients than in the control group of I~levich and Gleser, whilst in 3 different pain populations Egle et al. [ll] mainly found a preferential deployment of Turning Against the Object, Turning Against the Self and Projection compared to a student control group. The values for Reversal and Principalization were clearly lower than for the control group. These few studies with defence mechanisms have produced conflicting results with respect to pain. In this study we investigated the relationship between childhood experience, depression and defence mechanisms in a sample of chronic pain patients, and compared them to a series of psychiatric patients without major complaints of pain.

Patients and method Two groups of patients, described further below, were asked to complete a set of forms as follows. Patients with chronic pain were asked to complete a form seeking details of their pain, and also a set of psychological test forms. Patients without chronic pain but with psychiatric illness

were asked to complete the same set t,f psycholitgical test forms. These were: the Defense Mechanisms Inventory (DMI) [ 17,191, which was described above; a revised version of the Parental Bonding Instrument (PBI) [l&33]; and the Hospital Anxiety and Depression Scale (HAD) 1561. The PBI is a reliable and valid questionnaire il~strument for measuring the quahty of parent,,’ child relationships [32]. In reviewing the literature. Parker [32] suggests 2 major components in the parental contribution to the bonding between parent and child: care versus indifference or rejection, and overprotection versus encouragement 01 independence. The PBI comprises 25 questions for each parent, using a Likert-type format. It is scored for care and overprotection for each parent. WC offer a detailed discussion of the interaction btitween the DMI and the PBI in our related paper [46]. The scales of the PBI have shown relationships with other psy~hologi~a1 measures in ii number of studies including some on patients with pain 1291. The HAD is a 14-item questionnaire which measures anxiety and depression and is especially designed for patients suffering from a physical disorder because it avoids symptoms like insomnia, pain or anorexia that might result from physical illness as well as from a mood disorder. It has good reliability and validity [41,42]. The patients reflect consecutive samples of convenience and are highly selected. They comprise chronic pain patients referred to one of us (H.M.): patients without pain referred to H.M. for psychiatric advice; and patients from the open clinic at this psychiatric hospital. Almost all of the pain patients had been through a series of other referrals to neuroiogists, orthopaedic surgeons, neurosurgeons, or anaesthetists’ nerve block clinics. The other patients seen by H.M. must also he assumed to be selected. The patients attending the open clinic were often in social and financial difficulties and had reduced contact with their regular general practitioners. From May 1988 to November 198X 65 chronic pain patients received forms and 60 returned them. Forty-nine other psychiatric patients were given forms by H.M. and 31 returned them. In the hospital open out-patient clinic 70 sets of forms

165

were distributed and 34 returned. Thus the return rate for the pain patients was 92%; that for H.M.‘s other psychiatric patients 61%, and that for the patients from the hospital open out-patient clinic 48%. Evidently the pain patients returned the highest proportion of forms, perhaps reflecting their greater interest in the package which for them also included many details of their bodily complaints. The patients with pain, group P, have been compared with the remainder, group R.

Results One hundred and twenty-five forms which were returned by 14 November 1988 were reviewed. Eleven patients were excluded from the study, either because of their difficulties with the English language (N = 2) or because they responded very incompletely to the measures (N = 9). We have analysed the same forms as in our other study [46]. One hundred and fourteen sets of tests were evaluated. Two of the patients excluded had been referred for chronic pain, so that there were 58 pain patients (group P) and 56 other patients (group R). The average age for the pain population was 45.3 years, and for the other population it was 41.3 years. In both groups there were 20 male patients, in the pain group 38 females, in the other group 36 female patients. This sex distribution is in accordance with what is often found in psychiatric clinics. For all tests, internal correlations were in the expected direction, as shown elsewhere [46]. The results for the pain patients are generally nearer to those of a general population than those of the group R. A comparison of the clinical diagnoses reveals that pain patients have no current psychiatric diagnosis significantly more often than the patients of group R (Table I). Table II shows that both groups are more anxious than the general population, but they are similar to each other. Both groups also show signs of depression, but pain patients are significantly more depressed than the others. However, the latter have a number of other diagnoses such as personality disorder and schizophrenia.

TABLE

I

DIAGNOSES

Group P

Group R

21 30 15

13 27 8

1

0

1

0

1 11 1 0 0 0 1 0 0 1 0 0

6 5 2 4 1 1 10 1 2 1 6 6

No psychiatric disorder Affective disorder/anxiety Major affective disorder Major affective disorder + phobia Major affective disorder + hypochondriasis Bipolar disorder Atypical affective disorder Chronic anxiety Dysthymic personality disorder Obsessional personality disorder Hypochondriasis Personality disorder Schizoid Dependent Histrionic Other Schizophrenia

Group

P

Psychiatric diagnosis No psychiatric diagnosis

31 27

Comparisons

exact test.

with Fisher’s

Group

P

R

43 13

ns < 0.03

Some findings with regard to parental care are shown in Tables III and IV. Within our own samples, groups P and R have equivalent proportions of males and females. We have therefore combined the male and female scores on the PBI

TABLE

II

HOSPITAL ANXIETY MEAN SCORES Pain (P) patients patients (N = 56).

Anxiety Depression

AND DEPRESSION

(N = 58) compared

Pain P

Psychiatric R

10.1 9.7

10.5 7.4

SCALE (HAD):

to remainder

(R)

of

P

Normal values: i 7; suspected anxiety and depression: definite anxiety and depression: > 10. ns = no significance at P i 0.05, 2-tailed test.

7-10;

PARENTAL

BONDING

Pain (P) patients patients.

INSTRUMENT

compared

to remainder

Pain P

Psychiatric R

i-4

5x

56

Maternal care Paternal care Mat. overprotection Pat. overprotection

23.1 22.2 13.2 11.9

20.0 15.8 14.5 14.3

ol psychiatric

(R)

P

ns 0.002 ns us

to compare both groups (Table III). Whilst maternal care is not significantly different for the two groups (despite the trend for more care in the P group), paternal care was markedly better in the pain group overall (P = 0.002). Table IV shows the differences between our own groups and a general practice sample studied by Parker [32,33]. A modified Bonferroni procedure was used to correct for the two multiple comparisons with the same group of general prac-

TABLE

ttce patients. The scores in females indicate relatively good parental care in Parker’s sample when compared with our patients in both groups, ours having lower care scores. In males with pain. parental care is the same as that found in general practice. The R group (i.e., our general psychiatric sample) had significantly lower scores for care. ~~ve~rotection is not evident in our pain group compared with general practice patients. hut our psychiatric group (group R) shows significant cvidence of overprotection among the women. As with the PBI, we are able to combine the results of males and females on the DMl because of equivalent proportions. They appear to establish different patterns of defence between the groups (Table V). Pain patients seem to use Turning Against the Self to a lesser extent and Reversal to a greater extent than our group R sample. Calculating Reversal and Principali~ati~~n together, as Juni [ZO] suggested, shows it higher significant difference and suggests that the difference may be more general. Although only 7 comparisons were made in this table, it seemed appropriate to apply a Bonferroni procedure, and

IV

PARENTAL. Comparison

BONDING

INSTRUMENT

of pain (P) and remainder

of psychiatric

(R) patients

to Parker’s

general

practice

(G) sample ._

Group

Pain I’

Psychiatric R

Parker’s general practice G -

Ft?~Wf~ N Mat. care Pat. care Mat. overprotection Pat. overprotection

3x 20.9 20.17 14.37 12.55

36 19.43 16.75 14.x5 15.63

279 27.1 24.3 12.9 12.7

IMill<, N Mat. care Pat. care Mat. overprotection Pat. overprotection

20 27.0 25.6 11.15 11.0

20 21.2 14.2 13.8 11.73

131 26.9 23.1 13.9 11.7

For comparison of P with R, see Table III. ns = not significant at P < 0.05, 2-tailed. Probabilities * Parker et al. [33].

based on a modified

P -_ *

Bonferroni

P/G

R/G

< 0.01

< 0.001

n5

c 0.001

n’\ n\

< 0.01 < 0.01

ns ns ns 1,s

c: 0.05 < 0.01 ns ns

procedure

(see text).

167

TABLE

V

DEFENSE

MECHANISMS

Pain (P) patients patients.

compared

INVENTORY to remainder

Pain P

Psychiatric R

N

58

56

TAO PRO TAS REV PRIN REV + PRIN TAO + PRO

33.1 35.9 39.9 44.5 46.4 91 .o 69.0

33.6 37.6 42.4 41.7 44.4 86.2 71.3

* A Bonferroni text.

correction

alters

of psychiatric

(R)

P

ns ns 0.033 * 0.051 * ?04* ns all probabilities

*

to ns. See

that altered all the probabilities to non-significant. Those which appeared significant before this correction was made have been tested for the pain patients by comparison with another source in the literature, as shown in Table VI below. TABLE

Discussion

VI

DEFENCE

MECHANISM

INVENTORY

Comparison of pain (P) and remainder groups with Gleser and Ihilevich’s general

of psychiatric (R) adult sample (G). P

Pain P

General adults * G

Female N TAO PRO TAS REV PRIN Mean ages

38 32.8 36.2 40.5 43.5 47.1 45.3

71 34.8 36.9 41.9 39.2 47.3 28.7

ns ns ns < 0.01 ns < 0.001 *

Mak N TAO PRO TAS REV PRIN Mean ages

20 33.8 35.6 38.9 46.6 45.2 45.6

43 39.4 38.4 34.4 39.6 48.4 23.0

< ns < < ns <

Group

Table VI presents our own findings for the pain patients by sex in more detail, gives the ages of the groups, and compares the results to a normal sample of Ihilevich and Gleser. Both female and male pain patients use si~fic~tly more Reversal than a general adult sample. This trend might be due to the greater age of our patients since the use of reversal increases with age [10,17,38,56]. Our male pain patients show more Turning Against the Self and less turning Against the Object than the normal sample of Gleser and Ihilevich. Turning Against the Object and Projection are negatively related to age [10,17,38,54]. Turning Against the Self is not altered by age but the trends for Reversal and Turning Against the Object seen in our pain patients may be attributed to the differences in age between them and the groups of Gleser and Ihilevich. Overall, the pain patients tended to show relatively normal or mature defences and this comparison with a normal sample supports the observations for Reversal, the strongest effect in Table V.

* Gleser and Ihilevich

[17].

P/G

0.05 0.05 0.01 0.001 *

A sample bias must be recognized. As mentioned, the patients were highly selected. The outpatient clinic sample should be expected to score high on measures of psychopathology compared with general practice populations or routine general hospital patients outside psychiatric departments. They would also be expected to score higher than the pain sample. The same is to be anticipated with respect to the patients without pain seen by H.M. Accordingly, we cannot assume that the present findings will generalize to all comparisons of patients with pain and those without pain. However, they may serve as one of the starting points on this topic. Although we found a number of statistically significant differences, these calculations were not entirely independent and so the nominal type 1 error rates are inflated. We have corrected for this somewhat in Table IV, attempting to balance type 1 rates against power. In Table V we have applied the most stringent Bonferroni correction. Table VI, which was intended as a partial test of the

findings of Table V, contains a relatively limited number of comparisons and a number of significant findings. Hence, we have not attempted to provide corrections in this tabte. The P group is different from the R group in 3 respects. They show more depression, better childhood experiences, and a preference for Reversal and Principalization in their defence mechanisms, as well as low scores on Turning Against the Self. There are 3 possible contributory factors for the relatively high rate of depression in the pain group. First, selection factors might have an important effect on the extent of depression seen by the investigators. As shown in a previous study 1291 pain patients at this hospital have a higher rate of depression compared with other local pain populations. Second, other psychiatric diagnoses are less common in pain groups but will dilute the scores for depression in the psychiatric non-pain group (group R). Third, it is plausible that if the depression in the pain group is less associated with abnormal early experience and personality disorder. it will be more likely to be due simply to chronic pain and disability. In a previous paper 1291 we showed that scores on the Irritability. Depression and Anxiety Questionnaire have only 3 modest link to the childhood experience of a population with chronic pain. Also in the present study, in contrast to the general psychiatric sample (group R). the opinion of our pain patients about the care they received in childhood is not different from that of a general practice population. By contrast our psychiatric out-patients scored significantly differently from the general practice sample. Thus again, for pain patients the disturbance in the family background seems to be less important in the aetiology of their depression and anxiety than for the psychiatric sample. The investigation of defence mechanisms reveals that the pain patients show a higher use of Reversat and, interestingly, although more depressed than our psychiatric patients, they showed a lower tendency to blame themselves. Likewise, Van Knorring [SO] found less guilt in depressed patients who were also suffering from pain than for his purely depressed sample. Our results suggest that pain patients are depressed in the sense of low mood, despondency and helplessness, but

that they show a different psychodynamic background than depressed patients not suffering from a chronic painful disorder. Indeed, if \vt’ look ;II the depression items of the HAD. 11 becomes obvious that they mainly assess the phenomenology of depression such as low mood. lack ,)t’ energy. reduced enjoyment, ~~~n~entrati(~l~ and in.terest, but not psychodynamic characteristics like self-depreciation or self-blame. Taking this with our results on childhood experiences of thcsc patients, we might argue that the depression of pain patients does not originate regularly in neglect or abuse in childhood that leads to self-depreciation. but can be seen as a consequence of the painful condition in adult life, which leads to increased anxiety and depression. Our male patients did show evidence of guilt II~ the increased scores for Turning Against the Self. However, the females did not show this and aggression is probably not turned inwards ;/s much as Engel and others have argued. Engel et al. [I I] found that pain patients, regardless of the origin of their pain, showed a higher tendency ti> external aggression (comparable with Turning Against the Object) than their control group. This corresponds with the findings by Merskey [25] of ittcreased external resentment in pain patients. but not much guilt, although Spear [44] found no increase in covert or overt hostility in pain patients. Our pain patients show the highest tendency of all the groups which we have compared with them to use the defences included in Reversal. This result is in accordance with Mendelson [24] who found Reversal in his pain patients to be higher than in the normal population of Gleser and Ihilevich. One possible explanation, ;1s noted above, is the higher age of our population. Passchier et al. [35] found no differences in the DMI between pain populations and a control group. that was comparable with respect to age. Furthermore. other studies have shown that reversal seems to be an important defence mechanism in coping with a chronic illness. Reversal is negatively correlated with preoperative fear. days in bed after operation and demands for pain medication [54]. Women relying most on Reversal and Principalization showed lower premenstrual discomfort [ 1gf

169

than those using Turning Against the Object and Projection. Reversal seems to be a successful defence in terms of perception of health and survival after myocardial infarction [37]. As well Reversal has been found to defend most successfully against anxiety [7,17,37,38]. Our study indicates that depression in pain patients can be seen as an effect of pain on the mood of the patients. Their preference for using Reversal compared to the control sample of Gleser and I~le~ch can partly be attributed to their significantly higher age and is consistent with other studies on age and the DMI. Vaillant [46] found a shift from more immature to more mature defences with age. As we have concluded in a related paper, Reversal and P~ncipalization are the most mature defences in the DMI in terms of Vaillant’s ranking. Our results support the view that the defences employed by our pain patients are not more disturbed than those of a general population and indeed, less disturbed than that of patients who attend a psychiatric clinic. Their use of defence mechanisms is more comparable to a normal population than to a psychiatric population.

Elisabeth Tauschke was supported by a research fellowship from the FAZIT-Stiftung, Federal Republic of Germany. We thank Dr. Viera Barta and the staff of the Mental Health Clinic at London Psychiatric Hospital, who selected and diagnosed the patients in the clinic series and Ms. Mai Why, who provided extensive bibliographical help.

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