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Patterns of psychophysiological change in the treatment of agoraphobia
OOOS-7967/82/040347-iO803.00/0 Copyright 0 1982 Pergamon Press Ltd
5ehau. Res. The?. Vol. 20. pp. 347 to 356. 1982 Printed in Great Britain. All rights reserved
PATTERNS OF PSYCHOPHYSIOLOGICAL CHANGE IN THE TREATMENT OF AGORAPHOBIA Western
MATIG MAVESAKALIAN and LARRY MICHELSON Psychiatric Institute and Clinic, University of Pittsburgh, School of Medicine, Department of Psychiatry. 3811 O’Hara Street, Pittsburgh, PA 15261, U.S.A. (Received 2 September
t981)
Summary-Patterns of change and synchrony were studied in a group of 26 agoraphobics undergoing a 12-week treatment program. Clinical, behavioral, physiological and subjective measures were taken at pre-, 4, 8 and 12 weeks of treatment and at l-month follow-up. Clinically and statistically significant changes were found in all response systems and our results tentatively suggest that the order of change starts with behavioral and clinical measures followed by psychophysiological measures of which psysiological responsivity has the longest lag. Although the group as a whole changed synchronously, there was evidence of individual desynchrony between physiological and subjective measures of anxiety. The most common form this took was for SUDS to decline while heart rate increased. A closer look at desynchrony in the various time sequences revealed that both the form and occurrence of desynchrony vary according to phase of treatment and that time interval between assessment points might-be of crucial importance in the determination of synchrony-desynchrony.
INTRODUCTION
The realization that phobic anxiety is comprised of three response systems, which have complex interrelations, has important theoretical and clinical implications (Lang, 1968, 1977; Rachman and Hodgson, 1974; Hodgson and Rachman, 1974). The dimensions of concordance-discordance and synchrony-desynchrony have been utilized to represent correlations among different anxiety measures within an assessment trial and directional commonality of change in different anxiety measures across two or more assessment trials, respectively. The nature of the relationship between behavioral, physiological and cognitive response systems of anxiety, however, has eluded definition and has been repeatedly observed that in some individuals they correlate while in others they no not. Lietenberg er a/. (1971). in an elegant series of single case studies, demonstrated both synchronous and desynchronous changes between behavioral and physiological (heart rate) measures in the treatment of simple phobias, mainly claustrophobia. Recently, Barlow et al. (1980) reported various patterns of synchrony and desynchrony between heart rate and seif-report of anxiety, measured during a standard behavioral course at pre-, mid- and post-treatment in three agoraphobics undergoing a If-week treatment program. It was found that only one patient evidenced synchronous changes between heart rate and subjective anxiety. The remaining two patients had desynchronous changes, with one improving on subjective anxiety but not heart rate and the other patient improving on heart rate, but not subjective anxiety. Another type of desynchrony, namely, the possibility that the different response systems might have different rates of improvement with treatment can be best studied in groups of patients. Furthermore, alternative treatments may effect differential patterns and rates of change in the different response systems. For instance, in the pharmacological treatment of agoraphobia it has often been suggested that imipramine suppresses panic attacks. which is then followed by behavioral gains. Similarly, the behavioral treatment of agoraphobia with prolonged in-ciuo exposure aims at reducing avoidance behavior and presumes physiological habituation to take place initially, followed by subjective improvement. Repeated measures within and across response systems, taken at pre-. during and post-treatment, are likely to shed important light on synchronydesynchrony issues and highlight the presumed specificity of different treatment modalities. 347
348
MATE
MAVISSAKALIANand
LARRY MICHELSON
The purpose of this study is to explore possible differences in the rates with which physiological, behavioral and subjective measures of agoraphobia respond to treatment and to study individual patterns of synchrony and desynchrony between these various response systems. METHOD
Subjects The Ss of this study were selected from 26 agoraphobics who had completed their treatment phase and l-month follow-up assessments of a larger ongoing project which utilizes a 2 x 2 factorial design to compare the effectiveness of the following treatments: (1) imipramine (I); (2) flooding (F); (3) combined imipramine-flooding (IF); and (4) nonspecific treatment factors (NS). All patients met DSM-III diagnostic criteria for agoraphobia and were markedly incapacitated by their disorder. They were all female, with a mean age of 39 and a mean duration of illness equal to 11 yr. In all cases the onset of illness was before age 40 and the duration of illness was more than 1 yr. Treatment Treatment consisted of 12 weekly sessions of 15-min individual contact with a psychiatrist (MM) to adjust drug treatment (double-blind imipramine or placebo) and a 90-min group session with a psychologist (LM) in either in-uiuo flooding or group discussion. All patients received the same therapeutic rationale and instructions to practice in-l;ivo exposure between sessions. Drug treatment Patients were assigned to either imipramine or matched placebo, according to a predetermined randomization order known only to the hospital pharmacist. In the weekly individual sessions, one tablet of imipramine 25 mg or placebo was prescribed at bedtime and increased by 25 mg increments every second day until a tolerable maintenance dosage or a maximum of 200 mg (8 tablets) was reached. The average daily maintenance dosage of imipramine attained (in most instances by week 4) was 125 mg (range 25-200). ~eh~~~ora~treatment In addition to the individua1 sessions, patients, in groups of eight, were assigned alternatingly to either flooding or discussion conditions. In the flooding condition, they were encouraged to enter their most phobic situations either alone or with the assistance of the therapist at first. This typically involved going to the center of town, visits to department stores and shopping malls, bus rides and walking in congested areas alone pninterruptedly for longer and longer distances. The patients assigned to the group discussion met with the same therapist for general discussion of their phobias and their progress. instructions and reinforcement for self-controIled jn-~i~o practice were repeatedly given and general practical suggestions such as engqging the help of a friend or spouse and/or selecting certain specific phobic situations for that particular week’s practice were offered. However, specific cognitive strategies such as paradoxical intention or self-statement training were not given. All group therapy sessions lasted 90 min. Therapeutic instructions All patients were given the same therapeutic rationale and instructions. Briefly, they were told that the reason why their fears had continued and even increased with time was due to their habitual avoidance behavior and that in order to overcome their fears and anxieties they should stop avoiding and start entering their phobic situation, they should remain there and tolerate the anxiety-discomfort until it decreased to fairly confortable levels and/or until their urge to escape abated (i.e. habituation took place). They were also told that it is a good principle to proceed with their self-controlled exposure practices along a hierarchy from the least to the most phobic situations. Their progress was
Treatment of agoraphobia:
psychophysiological
349
change
Table 1. Treatments Subgroups
lmipramine
Flooding
Combined
Control
Pre-Follow-up (N = 13)
3
4
2
4
4-8-12 (N = 11)
3
2
5
1
Pre-4-8-12-Follow-up (N = 6)
2
1
2
1
reviewed weekly, reported gains in improvement were reinforced and patients were encouraged to proceed with their self-controlled in-uiuo practices. Furthermore, it was emphasized to them that whatever additional treatment they received, such as the drugs and group treatments, was designed to facilitate their carrying out elf-controlled in-vivo exposure practices. Only six patients had a complete set of heart-rate data including pretreatment, 4, 8, 12 weeks of treatment and at l-month follow-up. Therefore, we subdivided the sample into two subgroups, the first composed of 13 patients who had completed pre- and l-month follow-up heart-rate assessments, and the second composed of ll-patients who had completed the set of 4-, 8- and 12-week assessments. The treatment composition of the patients in the various subgroups is shown in Table 1. Assessments Major assessments were done at pretreatment, at 4-8-12 weeks of treatment, l-month follow-up. The measures reported in this paper include:
and at
1. ~e~uv~~~ff~meuswes. This direct measure of agoraphobia consisted of a standardized behavioral course 0.4 miles in length leading from the front door of the hospital to a crowded urban center and ending at a congested bus stop. Patients were asked to walk the course alone as far as they could go and to return only when their level of anxiety reached a degree which could not be tolerated. The course was divided into 20 steps and the performance was scored by assigning the number of the last step completed. At each step patients also rated their anxiety on a g-point SUD (Subjective Unit of Discomfort) Scale. The SUDS scores of the completed steps were averaged to yield the mean SUDS value. In addition, the peak SUDS and last step SUDS at each assessment were computed, Furthermore, the last step at pretreatment was indexed to provide an indexed step SUDS at subsequent assessments. 2. Heart-rate measure. During the standardized behavioral test a continuous record of heart rate was obtained using the Exersentry Model EX-3. The reliability of the Exersentry as a heart-rate measure has been recently assessed (Leelarthaepin et al., 1982). By setting the low heart-rate limit very high we obtained a continuous measure of heart rate which was recorded on a tape recorder and which then was replayed and analyzed as minute-by-minute heart rate. Heart-rate monitoring started with a 5-min resting baseline followed by a 5-min walking baseline during which the patients walked at their normal pace with a research assistant within the hospital. This was followed by the behavioral course. Several heart-rate indices were selected for analysis. These included: (1) a mean heart rate for the entire course; (2) heart-rate response which was the difference of the mean heart rate during the behavioral course and the mean heart rate during the walking baseline; (3) peak minute heart rate during the behavioral course; (4) last minute heart rate at each assessment; and (5) indexed heart rate which consisted of indexing the last completed minute of the behavioral course at pretreatment across repeated subsequent assessments (i.e. if the behavioral course lasted 6 min at pretreatment then the 6th min of the behavioral course at subsequent assessments constituted the indexed minute heart rate).
350
MATIG
MAVISSAKALIAN
and LARRY
MICHELSON
A brief rationale for the choice of the various heart-rate and SUDS indices might be in order. Heart-rate response was primarily used to control for exercise effect at each assessment and drug effect across assessments. Peak heart rate supposedly measures the most intense response, however, in the context of the in-uico behavioral course, this conclusion remains questionable because of various uncontrolled environmental stimuli which might temporarily increase heart rate. Recognizing the lack of perfectly synchronized measures of heart rate and subjective anxiety at each step (such as the Medilog recorder provides), we introduced the measures of last minute heart rate and indexed heart rate (as well as last step SUDS and indexed SUDS) to generate anchoring points during the behavioral course. Of these indices, the last minute or step measures presumably consist of the most ‘phobic’ events at each assessment, but are likely to change across assessments. However, the indexed measures provide more stable idiographic temporospatial reference points across assessments. 3. Clinical scales. In addition to the agoraphobia subscale of the Fear Questionnaire (Marks and Mathews. 1979), patients rated their five major and most severe phobic situations on a g-point rating scale of Phobic Anxiety and Avoidance following the practice introduced by Marks and Gelder (1965) and later modified by Watson and Marks (1971). The scores of the five situations were averaged to yield a mean clinical measure of phobic anxiety and avoidance.
RESULTS
Pretreatment-l-month
follow-up
subgroup
The mean minute-by-minute heart rate and step-by-step SUDS values of the 13 patients are presented in Figs 1 and 2 which show that resting baseline heart rate is lower than walking baseline which in turn is lower than heart rate during the behavioral course at both pre- and l-month follow-up assessments. Furthermore, it can be seen that, in general, both heart rate and SUDS values obtained in the behavioral course are lower at l-month follow-up than at pretreatment. However, the graphs should be viewed with caution because of individual differentes in steps completed at the different assessments. The results of matched pair t-test comparisons of the various measures, as shown in Table 2, reveal substantial improvement on all heart rate and SUDS measures. In addition, it can be seen that significant improvement on clinical agoraphobia scales was accompanied by significant changes on the behavioral measure, all SUDS measures and 3 out of 5 heart-rate measures. Upon examining individual patterns of change, it was observed that in three patients, mean heart rate at follow-up was higher than at pretreatment. In one SUDS had increased synchronously with heart rate. In the other two, SUDS had declined, thus 140 E
130-
p" I20 L Ilod) z IOOL ;0'
go80 -
-
Pro
-
Follow-UP
70-
Fig.
1. Mean
minute-by-minute heart beat on standardized and l-month follow-up for 13 agoraphobics
behavioral course at pretreatment (mixed treatment).
Treatment of agoraphobia:
psychophysiological
O-J , , , , , , , , , , , , I
2
3
4
5
6
7
8
9
IO
II
Standardized Events
r
12
13
,
351
change
-
Prc
-
Follow-up
,
14 I5
,
,
,
‘
,
I6
I7
19
I9
20
Behavioral Course
Fig. 2. Mean SUDS at each event on standardized
behavioral course at pretreatment l-month follow-up for 13 agoraphobics (mixed treatment).
and
creating a desynchronous picture. One of them had been treated in the flooding condition and the other had received nonspecific treatment. 4-8-l .? weeks subgroup The mean minute-by-minute heart rate and step-by-step SUDS values assessed at 4, 8 and 12 weeks in these 11 patients are presented in Figs 3 and 4. As can be seen there is a step-wise decline in these measures with treatment. In addition, since all the patients completed the behavioral course at all assessments, these figures reflect an adequate profile of psychophysiological responsiveness during the standardized behavioral course. Thus, it appears, that SUDS levels usually stay at the same IeveI during the entire course. On the other hand, heart rate seems to increase gradually and end up higher at the end of the behavioral course. That this apparent discordance could be due to an exercise effect cannot be ruled out with absolute confi-
Table 2. Matched pair r-tests comparing heart rate and anxiety at pretreatment l-month follow-up
and
Follow-up
Pre X
SD
Y
SD
f Value
122.03 10.92 127.31 127.08 131.46
13.99 7.87 16.39 17.10 16.47
110.21 9.75 115.85 111.17 122.62
17.02 10.74 18.10 17.66 20.74
2.75* 0.39 2.25* 2.60’ 1.43
Su/rjectioe Unit of Disturbance measures Mean SUDS 3.08 Last step SUDS 3.42 Indexed SUDS 3.42 4.42 Peak SUDS
1.89 2.84 2.84 2.07
1.03 1.17 0.83 1.83
1.18
1.40 1.11 1.75
3.34.’ 2.63* 2.98** 3.43**
1.69
0.64
2.35
1.91
10.43***
31.55
6.76
12.91
11.24
5.38***
13.67
6.87
18.25
4.09
Heart-rate measures
Mean heart rate Heart-rate response Last minute heart rate Indexed heart rate Peak heart rate
Phobia measures Phobic Anxiety and Avoidance Fear Questionnaire Agoraphobia Subscale Behavioral course steps completed
* P < 0.05; ** P $0.01; *** p < O.o()l.
2.86;
352
MATIG MAVISSAKALIAN and LARRY MICHELSON
x----J-
d
loo-
go-
-4 -8 -
12
60 I 1 I 1 I I 1 I I 1 I I 1 I I , I I I I I , 1 I I 1 I I I I s IO 15 20 25 30
Fig. 3. Mean
Resting
Walking
Baseline
Baseline
Slondardizsd
Behavioral
Course
Min
minute-by-minute heart beat on standardized behavioral course weeks of treatment for 11 agoraphobics (mixed treatment),
at 4. 8 and
12
dence. This, however, seems unlikely since with maintained exercise the tendency is toward stabilization and even decline of the heart-rate level (Jennings, 1981). Furthermore, there were no uphill stretches in the behavioral course and patients were repeatedly instructed to walk at their normal pace. An alternative explanation is that the behavioral course was indeed graded along a phobic continuum, as suggested by the heart-rate profile. This hypothesis is supported by the observation (see Tables 2 and 3) that the indexed heart rate and SUDS values were consistently lower than their respective last minute and step values, which also suggests that heart rate could be a more sensitive measure to small variations in the intensity of phobic stimuli. Repeated measures analysis of variance were performed across 4-8-12 assessment phases to ascertain whether there were any overall differences over time. The results yielded statistically significant differences for many of the dependent measures. To identify which comparisons (e.g. 4-8; 8-12; 4-12) were responsible for the overall significance, post-hoc r-tests were performed thereby permitting a more careful delineation of the temporal patterns of change. The results, as presented In Table 3, indicate that substantial improvement occurred on all measures (except on the behavioral course as the patients of this subgroup completed all 20 steps of the test on all occasions). On mean and peak heart-rate measures, only the 4-12 comparisons were significant. Similarly, significant changes were found on three out
0
I
I
,
I
I
2
3
4
1
,
,
5 6
,
1
1
,
7 6
9
IO
II
Standardized Course Fig. 4. Mean
SUDS
at each event on standardized treatment for I I agoraphobics
,
,
I2 I3
,
,
,
,
14 I5 16 I7
,
19
1
,
19 20
Behavioral Events behavioral course at 4. 8 and (mixed treatment).
12 weeks
of
Treatment of agoraphobia: Table 3. Matched pair r-tests comparing
psychophysiological
Week 8
Week 12
x
SD
x
SD
x
SD
Comparisons
142.75 18.25 149.01 138.13 159.36
29.13 18.34 33.43 30.98 28.94
130.86 15.61 137.64 134.13 f46.64
14.11 10.25 19.02 20.97 18.84
121.70 15.22 131.90 128.00 133.45
15.79 11.61 18.51 20.58 18.80
4 vs 12* NS NS NS 4 vs 12*
measures
Mean heart rate Heart-rate response Last minute heart rate Indexed heart rate Peak heart rate Subjectioe
353
heart-rate and anxiety measures at 4-8-12 weeks of treatment
Week 4
Heurt-rute
change
Unit
of Disturbance
measures
Mean SUDS
2.85
2.32
2.05
1.89
1.69
1.64
Last step SUDS Indexed SUDS Peak SUDS
2.27 1.78 3.91
2.00 1.72 2.63
1.64 1.44 2.73
I .43 1.24 2.28
1.09 0.67 1.64
1.51 0.87 1.86
4.57
1.45
3.56
1.07
2.36
1.30
4 vs 8* 8 vs 12** 4 vs 12***
Fear Questionnaire Agoraphobia Subscale
21.56
8.46
17.89
7.91
13.91
6.88
4 vs 8* 4 vs 12**
Behavioral course steps completed
20.00
0.00
19.55
1.04
20.00
0.00
NS
Phobia
8 vs 128 4 vs 12** 4 vs 12* NS 8 vs 12* 4 vs 12**
measures
Phobic Anxiety and Avoidance
* P G 0.05: ** P < 0.01; *** P g 0.001. NS. No significant difference.
of the four SUDS measures at 4-12 week assessment comparisons. Additionally, however, 8-12 comparisons were also significant on mean and peak SUDS measures. The clinical measures, however, yielded significant differences in 4-8 and 4-12 comparisons, with phobic anxiety and avoidance also achieving statistical significance at the 8-12 comparison. A closer look at individual patterns revealed that 5 out of 11 patients evidenced desynchrony between 4 and 8 weeks assessments. In three, SUDS had declined whereas mean heart rate had increased and in two, heart rate had declined when SUDS had increased. Both of these patients had received the combined treatment. Four out of the 11 patients evidenced desynchrony between 8 and 12 weeks assessment. In three, heart rate had increased when SUDS had declined and in one, heart rate had declined when SUDS had increased. This last patient was assigned to the nonspecific condition. Finally, 3 out of the II patients evidenced desynchrony in the 4-12 period. In two of them, heart rate had increased when SUDS had declined and in one, heart rate had declined when SUDS had increased. This patient had received the combined treatment. Pre-4-8-12-
1-month follow-up
subgroup
Figure 5 presents the findings in the subgroup of six patients who had completed all five heart-rate assessments. The heart-rate measure chosen in this instance was the heartrate response, to control for possible imipramine effect on absolute heart rate at the 4-8-12 assessments. Phobic Anxiety and Avoidance declined steadily in a step-wise fashion from pretreatment to the 12-week assessment with this gain being maintained at l-month follow-up. On the behavioral course measure it can be seen that within the first 4 weeks of treatment the mean steps completed for the group increased from 17 to the maximum of 20 which was maintained at all subsequent assessments. Heart-rate and SUDS responses, however, seemed to evidence an increase from pretreatment to 4th week of treatment.
354
MARC MAVISSAKALIAN and LARRYMICHEWON
Phobic avoidance
anxiety
and (maximum-8.0)
S- BAT (maximum20) Hsorr rate response ibpm)
S-SUDS
0
’
I
I
Pretreatment
4th
1
week
8th
I
week
Posttreatment
(maximum-8.0)
I
Follow-up
Fig. 5. Group mean values of phobic anxiety-avoidance, steps completed (S-BAT). mean SUDS (S-SUDS) and heart-rate response at pretreatment. 4. 8 and 12 weeks of treatment and l-month follow-up in six agoraphobics (mixed treatment).
Subsequently, however, both assessment. Concerning heart phobic range during the entire only at the l-month follow-up
measures declined steadily up to the l-month follow-up rate it is interesting to note that values remain in the course of treatment and decline below pretreatment levels assessment.
DISCUSSION
In discussing the results of the study, some of the difficulties in this type of research need to be mentioned. These are best illustrated by the fact that out of an initial pool of 32 patients, only 6 had a complete set of analyzable psychophysiological data across all assessments. Factors contributing to these difficulties are well known to clinical researchers and include drop-out and attrition rates, missing assessments and mechanical or technical failures during the assessments. In addition, the adaptation of the Exersentry in this study might have been partly responsible for the technical problems. Therefore, in our ongoing research we have been currently using the Medilog recorder which represents the state of the art in ambulatory heart-rate monitoring and provides perfect synchronization between heart rate and SUDS at each step of the behavioral course. Despite these difficulties, however, the present study represents one of the largest series evaluating psychophysiological response to a standardized in-km behavioral assessment test of agoraphobia to date. Furthermore, the method of analysis of the data which held subjects and drug effect constant across comparisons further enhances the significance of the present findings. The pre-follow-up comparisons in the 13 patients reveal that the group, as a whole, not only improved significantly on a clinical basis, but also across behavioral, physiological and subjective measures. Thus, on the whole, synchrony was obtained. Where individuai desynchrony was present, specifically in 2 out of the 13 patients (approx. 159;), it was in the direction of heart rate, showing an increase with SUDS declining. The 4-8-12 comparisons (Table 3) combined with the small group of six patients who completed all assessments, revealed interesting differential patterns of change across response systems. it thus appears that significant clinical improvement occurs early in treatment and continues steadily throughout.
Treatment of agoraphobia:
psychophysiological
change
355
Behavioral gains also occurred early in treatment. However, heart rate and SUDS did not show an improvement commensurate with behavioral improvement. Subsequent to week 4 however, SUDS improved steadily but this improvement reached significant levels only between 8 and 12 weeks of treatment. Heart rate also declined steadily from week 4 on, but remained above pretreatment levels throughout the treatment phase and declined below this level only at the l-month follow-up assessment. This coupled with the observation that only 4-12 week comparisons showed significant heart-rate change would suggest that improvement in heart-rate response might take much longer to be consolidated, a hypothesis which is supported by the continued gains made at the l-month follow-up assessment on this measure. The differential rates of change observed in this study fit the prediction advanced by Hodgson and Rachman (1974): “It would appear, therefore, that the first beneficial effect of flooding is an ability to control unwanted responses at the behavioural level. Autonomic and subjective signs of distress, associated with non-avoidance, are then gradually extinguished over a period of days, weeks or months.” (p. 321) Although not all patients in this study received flooding, they were all instructed to practice prolonged expostire. Their treatment thus, had high-demand characteristics which might explain the discordance between behavioral and psychophysiological change found early in treatment. In the 4-8-12 comparisons, the 11 patients showed a synchronous pattern of improvement across the clinical, psychophysiological and subjective measures. However, as expected, there was individual desynchrony between heart rate and subjective anxiety. Thus, in the 4-8 comparison approx. 45% of the patients showed desynchrony. The corresponding figures for the 8-12 and 4-12 comparisons were 36 and 27%, respectively. These observations support the hypothesis advanced by Hodgson and Rachman (1974) predicting a greater tendancy for desynchrony in the earlier phases of treatment with a shift to more synchronous change in the later phases of treatment. Furthermore, comparisons between assessment points 1 month apart yielded more desynchrony than comparisons between assessments 2 months apart which in turn were higher on desynchrony than pre-l-month follow-up comparisons covering a 4 month period. This would suggest that period of time separating the two anchoring assessments could be of crucial importance in the determination of synchrony-desynchrony. Finally, although the differential patterns of change across treatments could not be studied in the present context, it was observed that of the 14 instances of synchrony, six received the combined treatment. Imipramine and nonspecific treatments had three each and flooding had only two. Furthermore, three out of the four instances of the rare form of desynchrony (heart-rate decrease accompanying SUDS increase) were found in the combined treatment. These observations tentatively suggest that the combined treatment might both increase the likelihood, and affect the form, of desynchrony. If this is found to be true, it might explain the significantly greater relapse rate encountered with the combined treatment in comparison to flooding (Zitrin et al., 1980). Clearly, these findings need replication and the additional questions they raise need further elucidation, Foremost on this list seems to be the study of differential patterns of psychophysiological change across the alternative treatments of agoraphobia and their implication for the long-term maintenance of treatment effects, Ack,lo~tledgenie,zr-This Mental Health.
research was supported in part by Grant MH 34177 from the National Institute of
REFERENCES BARLOWD. H., MAVISSAKALIAN M. R.
and SCHQFIELDL. D. f1980) Patterns of dcsynchrony in agoraphobia: preliminary report. Behac. Res. Ther. 18, 441448. HODGSONR. I. and RACHMANS. (1974) Desynchrony in measures of fear. Behac. Res. Ther. 12, 319-326. JENNINGSR. (1981) Personal communication.
a
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LANG P. J. (1968) Fear reduction and fear behavior: problems in treatmg a construct. In Rrsearch in Psychorherapy. Vol. 3 (Edited by SHLIENJ. M.). American Psychological Association. Washington, DC. LANG P. J. (1977) Physiological assessment of anxiety and fear. In Behacioral .Assessntent: ,N~W Directrons in Clinical Psychology (Edited by CONE J. D. and HAWKINSR. P.). BrunnerjMazel. New York. LEELARTHAEPIN B.. GRAY W. and CHESWOR~HE. (1982) Exersentry: an evaluation of Its cardiac frequency monitoring accuracy. Amt. J. Sports Sci. In press. LEITENBERG H., AGRASS.. BUTZ R. and WINCZE J. (1971) Relationship between heart rate and behavioral change during the treatment of phobias. J. ubnorm. Psychol. 78, 59-68. MARKSI. M. and GELDERM. G. (1965) A controlled retrospective study of behavior therapy in phobic patients, Br. J. Psq’clriat. Ill, 561-573. MARKS I. M. and MATHEWSA. M. (1979) Brief standard self-rating for phobic patients. &hat. Rrs. 7%~. 17, 263-267. RACHMANS. J. (1978) Fear und Courage. Freeman, San Francisco. RACHMANS. and HODGSONR. I. (19741 Synchrony and desynchrony in fear and avoidance. Briiur. Res. Tim. 12, 311-318. WATSON J. P. and MARKS I. M. (1971) Relevant and irrelevant fear in flooding: a crossover patients. Behao. Ther. 2, 275-395. C. M., KLEIN D. F. and WOERNERM. G. (I9801 Treatment of agoraphobia and imipramine. Archs gm. Psych&. 37, 63-72.
ZITKIN
study of phobic
with group exposure irt riro
5ehau. Res. The?. Vol. 20. pp. 347 to 356. 1982 Printed in Great Britain. All rights reserved
PATTERNS OF PSYCHOPHYSIOLOGICAL CHANGE IN THE TREATMENT OF AGORAPHOBIA Western
MATIG MAVESAKALIAN and LARRY MICHELSON Psychiatric Institute and Clinic, University of Pittsburgh, School of Medicine, Department of Psychiatry. 3811 O’Hara Street, Pittsburgh, PA 15261, U.S.A. (Received 2 September
t981)
Summary-Patterns of change and synchrony were studied in a group of 26 agoraphobics undergoing a 12-week treatment program. Clinical, behavioral, physiological and subjective measures were taken at pre-, 4, 8 and 12 weeks of treatment and at l-month follow-up. Clinically and statistically significant changes were found in all response systems and our results tentatively suggest that the order of change starts with behavioral and clinical measures followed by psychophysiological measures of which psysiological responsivity has the longest lag. Although the group as a whole changed synchronously, there was evidence of individual desynchrony between physiological and subjective measures of anxiety. The most common form this took was for SUDS to decline while heart rate increased. A closer look at desynchrony in the various time sequences revealed that both the form and occurrence of desynchrony vary according to phase of treatment and that time interval between assessment points might-be of crucial importance in the determination of synchrony-desynchrony.
INTRODUCTION
The realization that phobic anxiety is comprised of three response systems, which have complex interrelations, has important theoretical and clinical implications (Lang, 1968, 1977; Rachman and Hodgson, 1974; Hodgson and Rachman, 1974). The dimensions of concordance-discordance and synchrony-desynchrony have been utilized to represent correlations among different anxiety measures within an assessment trial and directional commonality of change in different anxiety measures across two or more assessment trials, respectively. The nature of the relationship between behavioral, physiological and cognitive response systems of anxiety, however, has eluded definition and has been repeatedly observed that in some individuals they correlate while in others they no not. Lietenberg er a/. (1971). in an elegant series of single case studies, demonstrated both synchronous and desynchronous changes between behavioral and physiological (heart rate) measures in the treatment of simple phobias, mainly claustrophobia. Recently, Barlow et al. (1980) reported various patterns of synchrony and desynchrony between heart rate and seif-report of anxiety, measured during a standard behavioral course at pre-, mid- and post-treatment in three agoraphobics undergoing a If-week treatment program. It was found that only one patient evidenced synchronous changes between heart rate and subjective anxiety. The remaining two patients had desynchronous changes, with one improving on subjective anxiety but not heart rate and the other patient improving on heart rate, but not subjective anxiety. Another type of desynchrony, namely, the possibility that the different response systems might have different rates of improvement with treatment can be best studied in groups of patients. Furthermore, alternative treatments may effect differential patterns and rates of change in the different response systems. For instance, in the pharmacological treatment of agoraphobia it has often been suggested that imipramine suppresses panic attacks. which is then followed by behavioral gains. Similarly, the behavioral treatment of agoraphobia with prolonged in-ciuo exposure aims at reducing avoidance behavior and presumes physiological habituation to take place initially, followed by subjective improvement. Repeated measures within and across response systems, taken at pre-. during and post-treatment, are likely to shed important light on synchronydesynchrony issues and highlight the presumed specificity of different treatment modalities. 347
348
MATE
MAVISSAKALIANand
LARRY MICHELSON
The purpose of this study is to explore possible differences in the rates with which physiological, behavioral and subjective measures of agoraphobia respond to treatment and to study individual patterns of synchrony and desynchrony between these various response systems. METHOD
Subjects The Ss of this study were selected from 26 agoraphobics who had completed their treatment phase and l-month follow-up assessments of a larger ongoing project which utilizes a 2 x 2 factorial design to compare the effectiveness of the following treatments: (1) imipramine (I); (2) flooding (F); (3) combined imipramine-flooding (IF); and (4) nonspecific treatment factors (NS). All patients met DSM-III diagnostic criteria for agoraphobia and were markedly incapacitated by their disorder. They were all female, with a mean age of 39 and a mean duration of illness equal to 11 yr. In all cases the onset of illness was before age 40 and the duration of illness was more than 1 yr. Treatment Treatment consisted of 12 weekly sessions of 15-min individual contact with a psychiatrist (MM) to adjust drug treatment (double-blind imipramine or placebo) and a 90-min group session with a psychologist (LM) in either in-uiuo flooding or group discussion. All patients received the same therapeutic rationale and instructions to practice in-l;ivo exposure between sessions. Drug treatment Patients were assigned to either imipramine or matched placebo, according to a predetermined randomization order known only to the hospital pharmacist. In the weekly individual sessions, one tablet of imipramine 25 mg or placebo was prescribed at bedtime and increased by 25 mg increments every second day until a tolerable maintenance dosage or a maximum of 200 mg (8 tablets) was reached. The average daily maintenance dosage of imipramine attained (in most instances by week 4) was 125 mg (range 25-200). ~eh~~~ora~treatment In addition to the individua1 sessions, patients, in groups of eight, were assigned alternatingly to either flooding or discussion conditions. In the flooding condition, they were encouraged to enter their most phobic situations either alone or with the assistance of the therapist at first. This typically involved going to the center of town, visits to department stores and shopping malls, bus rides and walking in congested areas alone pninterruptedly for longer and longer distances. The patients assigned to the group discussion met with the same therapist for general discussion of their phobias and their progress. instructions and reinforcement for self-controIled jn-~i~o practice were repeatedly given and general practical suggestions such as engqging the help of a friend or spouse and/or selecting certain specific phobic situations for that particular week’s practice were offered. However, specific cognitive strategies such as paradoxical intention or self-statement training were not given. All group therapy sessions lasted 90 min. Therapeutic instructions All patients were given the same therapeutic rationale and instructions. Briefly, they were told that the reason why their fears had continued and even increased with time was due to their habitual avoidance behavior and that in order to overcome their fears and anxieties they should stop avoiding and start entering their phobic situation, they should remain there and tolerate the anxiety-discomfort until it decreased to fairly confortable levels and/or until their urge to escape abated (i.e. habituation took place). They were also told that it is a good principle to proceed with their self-controlled exposure practices along a hierarchy from the least to the most phobic situations. Their progress was
Treatment of agoraphobia:
psychophysiological
349
change
Table 1. Treatments Subgroups
lmipramine
Flooding
Combined
Control
Pre-Follow-up (N = 13)
3
4
2
4
4-8-12 (N = 11)
3
2
5
1
Pre-4-8-12-Follow-up (N = 6)
2
1
2
1
reviewed weekly, reported gains in improvement were reinforced and patients were encouraged to proceed with their self-controlled in-uiuo practices. Furthermore, it was emphasized to them that whatever additional treatment they received, such as the drugs and group treatments, was designed to facilitate their carrying out elf-controlled in-vivo exposure practices. Only six patients had a complete set of heart-rate data including pretreatment, 4, 8, 12 weeks of treatment and at l-month follow-up. Therefore, we subdivided the sample into two subgroups, the first composed of 13 patients who had completed pre- and l-month follow-up heart-rate assessments, and the second composed of ll-patients who had completed the set of 4-, 8- and 12-week assessments. The treatment composition of the patients in the various subgroups is shown in Table 1. Assessments Major assessments were done at pretreatment, at 4-8-12 weeks of treatment, l-month follow-up. The measures reported in this paper include:
and at
1. ~e~uv~~~ff~meuswes. This direct measure of agoraphobia consisted of a standardized behavioral course 0.4 miles in length leading from the front door of the hospital to a crowded urban center and ending at a congested bus stop. Patients were asked to walk the course alone as far as they could go and to return only when their level of anxiety reached a degree which could not be tolerated. The course was divided into 20 steps and the performance was scored by assigning the number of the last step completed. At each step patients also rated their anxiety on a g-point SUD (Subjective Unit of Discomfort) Scale. The SUDS scores of the completed steps were averaged to yield the mean SUDS value. In addition, the peak SUDS and last step SUDS at each assessment were computed, Furthermore, the last step at pretreatment was indexed to provide an indexed step SUDS at subsequent assessments. 2. Heart-rate measure. During the standardized behavioral test a continuous record of heart rate was obtained using the Exersentry Model EX-3. The reliability of the Exersentry as a heart-rate measure has been recently assessed (Leelarthaepin et al., 1982). By setting the low heart-rate limit very high we obtained a continuous measure of heart rate which was recorded on a tape recorder and which then was replayed and analyzed as minute-by-minute heart rate. Heart-rate monitoring started with a 5-min resting baseline followed by a 5-min walking baseline during which the patients walked at their normal pace with a research assistant within the hospital. This was followed by the behavioral course. Several heart-rate indices were selected for analysis. These included: (1) a mean heart rate for the entire course; (2) heart-rate response which was the difference of the mean heart rate during the behavioral course and the mean heart rate during the walking baseline; (3) peak minute heart rate during the behavioral course; (4) last minute heart rate at each assessment; and (5) indexed heart rate which consisted of indexing the last completed minute of the behavioral course at pretreatment across repeated subsequent assessments (i.e. if the behavioral course lasted 6 min at pretreatment then the 6th min of the behavioral course at subsequent assessments constituted the indexed minute heart rate).
350
MATIG
MAVISSAKALIAN
and LARRY
MICHELSON
A brief rationale for the choice of the various heart-rate and SUDS indices might be in order. Heart-rate response was primarily used to control for exercise effect at each assessment and drug effect across assessments. Peak heart rate supposedly measures the most intense response, however, in the context of the in-uico behavioral course, this conclusion remains questionable because of various uncontrolled environmental stimuli which might temporarily increase heart rate. Recognizing the lack of perfectly synchronized measures of heart rate and subjective anxiety at each step (such as the Medilog recorder provides), we introduced the measures of last minute heart rate and indexed heart rate (as well as last step SUDS and indexed SUDS) to generate anchoring points during the behavioral course. Of these indices, the last minute or step measures presumably consist of the most ‘phobic’ events at each assessment, but are likely to change across assessments. However, the indexed measures provide more stable idiographic temporospatial reference points across assessments. 3. Clinical scales. In addition to the agoraphobia subscale of the Fear Questionnaire (Marks and Mathews. 1979), patients rated their five major and most severe phobic situations on a g-point rating scale of Phobic Anxiety and Avoidance following the practice introduced by Marks and Gelder (1965) and later modified by Watson and Marks (1971). The scores of the five situations were averaged to yield a mean clinical measure of phobic anxiety and avoidance.
RESULTS
Pretreatment-l-month
follow-up
subgroup
The mean minute-by-minute heart rate and step-by-step SUDS values of the 13 patients are presented in Figs 1 and 2 which show that resting baseline heart rate is lower than walking baseline which in turn is lower than heart rate during the behavioral course at both pre- and l-month follow-up assessments. Furthermore, it can be seen that, in general, both heart rate and SUDS values obtained in the behavioral course are lower at l-month follow-up than at pretreatment. However, the graphs should be viewed with caution because of individual differentes in steps completed at the different assessments. The results of matched pair t-test comparisons of the various measures, as shown in Table 2, reveal substantial improvement on all heart rate and SUDS measures. In addition, it can be seen that significant improvement on clinical agoraphobia scales was accompanied by significant changes on the behavioral measure, all SUDS measures and 3 out of 5 heart-rate measures. Upon examining individual patterns of change, it was observed that in three patients, mean heart rate at follow-up was higher than at pretreatment. In one SUDS had increased synchronously with heart rate. In the other two, SUDS had declined, thus 140 E
130-
p" I20 L Ilod) z IOOL ;0'
go80 -
-
Pro
-
Follow-UP
70-
Fig.
1. Mean
minute-by-minute heart beat on standardized and l-month follow-up for 13 agoraphobics
behavioral course at pretreatment (mixed treatment).
Treatment of agoraphobia:
psychophysiological
O-J , , , , , , , , , , , , I
2
3
4
5
6
7
8
9
IO
II
Standardized Events
r
12
13
,
351
change
-
Prc
-
Follow-up
,
14 I5
,
,
,
‘
,
I6
I7
19
I9
20
Behavioral Course
Fig. 2. Mean SUDS at each event on standardized
behavioral course at pretreatment l-month follow-up for 13 agoraphobics (mixed treatment).
and
creating a desynchronous picture. One of them had been treated in the flooding condition and the other had received nonspecific treatment. 4-8-l .? weeks subgroup The mean minute-by-minute heart rate and step-by-step SUDS values assessed at 4, 8 and 12 weeks in these 11 patients are presented in Figs 3 and 4. As can be seen there is a step-wise decline in these measures with treatment. In addition, since all the patients completed the behavioral course at all assessments, these figures reflect an adequate profile of psychophysiological responsiveness during the standardized behavioral course. Thus, it appears, that SUDS levels usually stay at the same IeveI during the entire course. On the other hand, heart rate seems to increase gradually and end up higher at the end of the behavioral course. That this apparent discordance could be due to an exercise effect cannot be ruled out with absolute confi-
Table 2. Matched pair r-tests comparing heart rate and anxiety at pretreatment l-month follow-up
and
Follow-up
Pre X
SD
Y
SD
f Value
122.03 10.92 127.31 127.08 131.46
13.99 7.87 16.39 17.10 16.47
110.21 9.75 115.85 111.17 122.62
17.02 10.74 18.10 17.66 20.74
2.75* 0.39 2.25* 2.60’ 1.43
Su/rjectioe Unit of Disturbance measures Mean SUDS 3.08 Last step SUDS 3.42 Indexed SUDS 3.42 4.42 Peak SUDS
1.89 2.84 2.84 2.07
1.03 1.17 0.83 1.83
1.18
1.40 1.11 1.75
3.34.’ 2.63* 2.98** 3.43**
1.69
0.64
2.35
1.91
10.43***
31.55
6.76
12.91
11.24
5.38***
13.67
6.87
18.25
4.09
Heart-rate measures
Mean heart rate Heart-rate response Last minute heart rate Indexed heart rate Peak heart rate
Phobia measures Phobic Anxiety and Avoidance Fear Questionnaire Agoraphobia Subscale Behavioral course steps completed
* P < 0.05; ** P $0.01; *** p < O.o()l.
2.86;
352
MATIG MAVISSAKALIAN and LARRY MICHELSON
x----J-
d
loo-
go-
-4 -8 -
12
60 I 1 I 1 I I 1 I I 1 I I 1 I I , I I I I I , 1 I I 1 I I I I s IO 15 20 25 30
Fig. 3. Mean
Resting
Walking
Baseline
Baseline
Slondardizsd
Behavioral
Course
Min
minute-by-minute heart beat on standardized behavioral course weeks of treatment for 11 agoraphobics (mixed treatment),
at 4. 8 and
12
dence. This, however, seems unlikely since with maintained exercise the tendency is toward stabilization and even decline of the heart-rate level (Jennings, 1981). Furthermore, there were no uphill stretches in the behavioral course and patients were repeatedly instructed to walk at their normal pace. An alternative explanation is that the behavioral course was indeed graded along a phobic continuum, as suggested by the heart-rate profile. This hypothesis is supported by the observation (see Tables 2 and 3) that the indexed heart rate and SUDS values were consistently lower than their respective last minute and step values, which also suggests that heart rate could be a more sensitive measure to small variations in the intensity of phobic stimuli. Repeated measures analysis of variance were performed across 4-8-12 assessment phases to ascertain whether there were any overall differences over time. The results yielded statistically significant differences for many of the dependent measures. To identify which comparisons (e.g. 4-8; 8-12; 4-12) were responsible for the overall significance, post-hoc r-tests were performed thereby permitting a more careful delineation of the temporal patterns of change. The results, as presented In Table 3, indicate that substantial improvement occurred on all measures (except on the behavioral course as the patients of this subgroup completed all 20 steps of the test on all occasions). On mean and peak heart-rate measures, only the 4-12 comparisons were significant. Similarly, significant changes were found on three out
0
I
I
,
I
I
2
3
4
1
,
,
5 6
,
1
1
,
7 6
9
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Standardized Course Fig. 4. Mean
SUDS
at each event on standardized treatment for I I agoraphobics
,
,
I2 I3
,
,
,
,
14 I5 16 I7
,
19
1
,
19 20
Behavioral Events behavioral course at 4. 8 and (mixed treatment).
12 weeks
of
Treatment of agoraphobia: Table 3. Matched pair r-tests comparing
psychophysiological
Week 8
Week 12
x
SD
x
SD
x
SD
Comparisons
142.75 18.25 149.01 138.13 159.36
29.13 18.34 33.43 30.98 28.94
130.86 15.61 137.64 134.13 f46.64
14.11 10.25 19.02 20.97 18.84
121.70 15.22 131.90 128.00 133.45
15.79 11.61 18.51 20.58 18.80
4 vs 12* NS NS NS 4 vs 12*
measures
Mean heart rate Heart-rate response Last minute heart rate Indexed heart rate Peak heart rate Subjectioe
353
heart-rate and anxiety measures at 4-8-12 weeks of treatment
Week 4
Heurt-rute
change
Unit
of Disturbance
measures
Mean SUDS
2.85
2.32
2.05
1.89
1.69
1.64
Last step SUDS Indexed SUDS Peak SUDS
2.27 1.78 3.91
2.00 1.72 2.63
1.64 1.44 2.73
I .43 1.24 2.28
1.09 0.67 1.64
1.51 0.87 1.86
4.57
1.45
3.56
1.07
2.36
1.30
4 vs 8* 8 vs 12** 4 vs 12***
Fear Questionnaire Agoraphobia Subscale
21.56
8.46
17.89
7.91
13.91
6.88
4 vs 8* 4 vs 12**
Behavioral course steps completed
20.00
0.00
19.55
1.04
20.00
0.00
NS
Phobia
8 vs 128 4 vs 12** 4 vs 12* NS 8 vs 12* 4 vs 12**
measures
Phobic Anxiety and Avoidance
* P G 0.05: ** P < 0.01; *** P g 0.001. NS. No significant difference.
of the four SUDS measures at 4-12 week assessment comparisons. Additionally, however, 8-12 comparisons were also significant on mean and peak SUDS measures. The clinical measures, however, yielded significant differences in 4-8 and 4-12 comparisons, with phobic anxiety and avoidance also achieving statistical significance at the 8-12 comparison. A closer look at individual patterns revealed that 5 out of 11 patients evidenced desynchrony between 4 and 8 weeks assessments. In three, SUDS had declined whereas mean heart rate had increased and in two, heart rate had declined when SUDS had increased. Both of these patients had received the combined treatment. Four out of the 11 patients evidenced desynchrony between 8 and 12 weeks assessment. In three, heart rate had increased when SUDS had declined and in one, heart rate had declined when SUDS had increased. This last patient was assigned to the nonspecific condition. Finally, 3 out of the II patients evidenced desynchrony in the 4-12 period. In two of them, heart rate had increased when SUDS had declined and in one, heart rate had declined when SUDS had increased. This patient had received the combined treatment. Pre-4-8-12-
1-month follow-up
subgroup
Figure 5 presents the findings in the subgroup of six patients who had completed all five heart-rate assessments. The heart-rate measure chosen in this instance was the heartrate response, to control for possible imipramine effect on absolute heart rate at the 4-8-12 assessments. Phobic Anxiety and Avoidance declined steadily in a step-wise fashion from pretreatment to the 12-week assessment with this gain being maintained at l-month follow-up. On the behavioral course measure it can be seen that within the first 4 weeks of treatment the mean steps completed for the group increased from 17 to the maximum of 20 which was maintained at all subsequent assessments. Heart-rate and SUDS responses, however, seemed to evidence an increase from pretreatment to 4th week of treatment.
354
MARC MAVISSAKALIAN and LARRYMICHEWON
Phobic avoidance
anxiety
and (maximum-8.0)
S- BAT (maximum20) Hsorr rate response ibpm)
S-SUDS
0
’
I
I
Pretreatment
4th
1
week
8th
I
week
Posttreatment
(maximum-8.0)
I
Follow-up
Fig. 5. Group mean values of phobic anxiety-avoidance, steps completed (S-BAT). mean SUDS (S-SUDS) and heart-rate response at pretreatment. 4. 8 and 12 weeks of treatment and l-month follow-up in six agoraphobics (mixed treatment).
Subsequently, however, both assessment. Concerning heart phobic range during the entire only at the l-month follow-up
measures declined steadily up to the l-month follow-up rate it is interesting to note that values remain in the course of treatment and decline below pretreatment levels assessment.
DISCUSSION
In discussing the results of the study, some of the difficulties in this type of research need to be mentioned. These are best illustrated by the fact that out of an initial pool of 32 patients, only 6 had a complete set of analyzable psychophysiological data across all assessments. Factors contributing to these difficulties are well known to clinical researchers and include drop-out and attrition rates, missing assessments and mechanical or technical failures during the assessments. In addition, the adaptation of the Exersentry in this study might have been partly responsible for the technical problems. Therefore, in our ongoing research we have been currently using the Medilog recorder which represents the state of the art in ambulatory heart-rate monitoring and provides perfect synchronization between heart rate and SUDS at each step of the behavioral course. Despite these difficulties, however, the present study represents one of the largest series evaluating psychophysiological response to a standardized in-km behavioral assessment test of agoraphobia to date. Furthermore, the method of analysis of the data which held subjects and drug effect constant across comparisons further enhances the significance of the present findings. The pre-follow-up comparisons in the 13 patients reveal that the group, as a whole, not only improved significantly on a clinical basis, but also across behavioral, physiological and subjective measures. Thus, on the whole, synchrony was obtained. Where individuai desynchrony was present, specifically in 2 out of the 13 patients (approx. 159;), it was in the direction of heart rate, showing an increase with SUDS declining. The 4-8-12 comparisons (Table 3) combined with the small group of six patients who completed all assessments, revealed interesting differential patterns of change across response systems. it thus appears that significant clinical improvement occurs early in treatment and continues steadily throughout.
Treatment of agoraphobia:
psychophysiological
change
355
Behavioral gains also occurred early in treatment. However, heart rate and SUDS did not show an improvement commensurate with behavioral improvement. Subsequent to week 4 however, SUDS improved steadily but this improvement reached significant levels only between 8 and 12 weeks of treatment. Heart rate also declined steadily from week 4 on, but remained above pretreatment levels throughout the treatment phase and declined below this level only at the l-month follow-up assessment. This coupled with the observation that only 4-12 week comparisons showed significant heart-rate change would suggest that improvement in heart-rate response might take much longer to be consolidated, a hypothesis which is supported by the continued gains made at the l-month follow-up assessment on this measure. The differential rates of change observed in this study fit the prediction advanced by Hodgson and Rachman (1974): “It would appear, therefore, that the first beneficial effect of flooding is an ability to control unwanted responses at the behavioural level. Autonomic and subjective signs of distress, associated with non-avoidance, are then gradually extinguished over a period of days, weeks or months.” (p. 321) Although not all patients in this study received flooding, they were all instructed to practice prolonged expostire. Their treatment thus, had high-demand characteristics which might explain the discordance between behavioral and psychophysiological change found early in treatment. In the 4-8-12 comparisons, the 11 patients showed a synchronous pattern of improvement across the clinical, psychophysiological and subjective measures. However, as expected, there was individual desynchrony between heart rate and subjective anxiety. Thus, in the 4-8 comparison approx. 45% of the patients showed desynchrony. The corresponding figures for the 8-12 and 4-12 comparisons were 36 and 27%, respectively. These observations support the hypothesis advanced by Hodgson and Rachman (1974) predicting a greater tendancy for desynchrony in the earlier phases of treatment with a shift to more synchronous change in the later phases of treatment. Furthermore, comparisons between assessment points 1 month apart yielded more desynchrony than comparisons between assessments 2 months apart which in turn were higher on desynchrony than pre-l-month follow-up comparisons covering a 4 month period. This would suggest that period of time separating the two anchoring assessments could be of crucial importance in the determination of synchrony-desynchrony. Finally, although the differential patterns of change across treatments could not be studied in the present context, it was observed that of the 14 instances of synchrony, six received the combined treatment. Imipramine and nonspecific treatments had three each and flooding had only two. Furthermore, three out of the four instances of the rare form of desynchrony (heart-rate decrease accompanying SUDS increase) were found in the combined treatment. These observations tentatively suggest that the combined treatment might both increase the likelihood, and affect the form, of desynchrony. If this is found to be true, it might explain the significantly greater relapse rate encountered with the combined treatment in comparison to flooding (Zitrin et al., 1980). Clearly, these findings need replication and the additional questions they raise need further elucidation, Foremost on this list seems to be the study of differential patterns of psychophysiological change across the alternative treatments of agoraphobia and their implication for the long-term maintenance of treatment effects, Ack,lo~tledgenie,zr-This Mental Health.
research was supported in part by Grant MH 34177 from the National Institute of
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and SCHQFIELDL. D. f1980) Patterns of dcsynchrony in agoraphobia: preliminary report. Behac. Res. Ther. 18, 441448. HODGSONR. I. and RACHMANS. (1974) Desynchrony in measures of fear. Behac. Res. Ther. 12, 319-326. JENNINGSR. (1981) Personal communication.
a
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LANG P. J. (1968) Fear reduction and fear behavior: problems in treatmg a construct. In Rrsearch in Psychorherapy. Vol. 3 (Edited by SHLIENJ. M.). American Psychological Association. Washington, DC. LANG P. J. (1977) Physiological assessment of anxiety and fear. In Behacioral .Assessntent: ,N~W Directrons in Clinical Psychology (Edited by CONE J. D. and HAWKINSR. P.). BrunnerjMazel. New York. LEELARTHAEPIN B.. GRAY W. and CHESWOR~HE. (1982) Exersentry: an evaluation of Its cardiac frequency monitoring accuracy. Amt. J. Sports Sci. In press. LEITENBERG H., AGRASS.. BUTZ R. and WINCZE J. (1971) Relationship between heart rate and behavioral change during the treatment of phobias. J. ubnorm. Psychol. 78, 59-68. MARKSI. M. and GELDERM. G. (1965) A controlled retrospective study of behavior therapy in phobic patients, Br. J. Psq’clriat. Ill, 561-573. MARKS I. M. and MATHEWSA. M. (1979) Brief standard self-rating for phobic patients. &hat. Rrs. 7%~. 17, 263-267. RACHMANS. J. (1978) Fear und Courage. Freeman, San Francisco. RACHMANS. and HODGSONR. I. (19741 Synchrony and desynchrony in fear and avoidance. Briiur. Res. Tim. 12, 311-318. WATSON J. P. and MARKS I. M. (1971) Relevant and irrelevant fear in flooding: a crossover patients. Behao. Ther. 2, 275-395. C. M., KLEIN D. F. and WOERNERM. G. (I9801 Treatment of agoraphobia and imipramine. Archs gm. Psych&. 37, 63-72.
ZITKIN
study of phobic
with group exposure irt riro