The Role Of Exposure Therapy In The Psychological Treatment Of PTSD
By Terence M. Keane, Ph.D.
NCP Clinical Quarterly 5(4): Fall 1995
Exposure treatments within cognitive-behavior therapy emerged in response to the need for more intensive, direct, and effective interventions for crippling anxiety and stress disorders. Successful in the treatment of agoraphobia, panic disorder, social anxiety, simple phobias, and obsessive-compulsive disorder, these therapies have more recently been applied to the treatment of post-traumatic stress disorder (PTSD). The purpose of this article is to describe the fundamentals of exposure therapy and its many variants, describe how it is used in the treatment of PTSD, and to offer guidelines for when to use this potentially very effective technique within a comprehensive approach to treating PTSD.
Behavioral and cognitive models for conceptualizing PTSD have already appeared in the literature (1-3). These models describe the premise from which one operates in using exposure treatments; this premise is critical to understand and appreciate before implementation of these treatments, but will not be reviewed here as it is beyond the scope of the article. Readers are referred to the primary sources to obtain the requisite background for using exposure treatments.
Definitions Of Exposure Therapy
There are many behavioral techniques that are circumscribed by the term exposure therapy including: systematic desensitization, in vivo and imaginal (4): flooding, in vivo and imaginal (5); implosive therapy (6); and certain extinction-based procedures such as graduated extinction (7), covert extinction (8), and participant modeling (7). Other techniques could also be readily understood as an exposure treatment, but were derived from models other than learning theory or experimental psychology and will not be included in this discussion (e.g. hypnosis, paradoxical intention). Eye movement desensitization and reprocessing (EMDR; 9), an essentially atheoretical technique, contains components of exposure therapy and cognitive therapy; due to its atheoretical basis and the specific training required for implementation, it will also not be reviewed here.
Systematic desensitization typically involves the pairing of relaxation with either images of the traumatic event (imaginal desensitization) or stimuli reminiscent of the traumatic event (in vivo desensitization). Returning to the scene of a traumatic event and gradually approaching the cues that are most evocative of the emotions associated with the traumatic event while practicing cued relaxation responses (e.g. deep breathing, relaxing imagery) would constitute "in vivo" exposure to traumatic cues. Careful construction of the graduated hierarchy in concert with the client permits the therapist to monitor the extent to which the client is successfully coping with the anxiety inducing cues and to determine if the client is ready for the next step on the hierarchy. Soliciting feedback from the client as each step of the hierarchy is broached while simultaneously encouraging the use of the relaxation helps the therapist to determine whether a particular step on the hierarchy has been mastered and if the client is prepared for the next step. When using desensitization the emphasis is clearly on a graduated approach to the traumatic cues coupled with the use of a competing cognitive or behavioral relaxation strategy (i.e., imagery or deep muscle relaxation).
Imaginal desensitization involves the use of imagery and follows the same fundamental principles as those used in "in vivo" desensitization. The obvious distinction is that imaginal desensitization utilizes memories, images, or other cognitive representations of the traumatic event. In both approaches the therapist constructs the hierarchy in conjunction with the client, and then moves to the next element of the hierarchy when and only when the client has mastered the previous element. There is input and feedback from the client throughout the process and this permits a client to experience control in the therapeutic process.
Flooding (5) can also be implemented either imaginally or "in vivo." It is typically defined as exposure to the traumatic cues to promote the experience of anxiety (or other aversive emotions) in the context of therapy. Clients approach the traumatic cues in the presence and safety of the therapeutic relationship, experience the emotions associated with the cues, experience the inevitable decline in affective experience (although this can sometimes take a considerable amount of time: 100 or more minutes), discuss alternative constructions of the event and its meaning, and repeat this sequence multiple times until the event or cues become increasingly less aversive.
Implosive therapy (6, 10) is an imaginal technique that promotes exposure to the original traumatic event using memory reactivation. When it is impossible to utilize 'in vivo" exposure, implosive therapy can effectively provide the medium for accessing traumatic memories. Implosive therapy is distinguished from imaginal flooding by virtue of its use of cognitive variables that are correlated with the development of PTSD (e.g., hopelessness, loss of control, etc.). These variables can be central to the development and maintenance of traumatic symptomatology and thus crucial to introduce in the exposure therapy to evoke the affective response and initiate emotional processing of the event.
While other exposure based techniques such as participant modeling and image habituation (11) have been examined in the treatment of PTSD, more precise details of technique implementation can be obtained from the original sources. Readers will notice the extensive overlap with the theoretical premises of the above techniques as well as procedural similarities. Most impressive in the single case applications of these approaches is the creativity of therapists in focusing upon the key symptoms of clients and developing a technique that promotes exposure in the most optimal way, thus contributing to the alleviation of symptom complaints in their clients. This flexibility comes from first, an appreciation of the theoretical mechanisms underlying the use of exposure treatments, and second, experience in conducting exposure therapies. Equipped with these two prerequisites, a competent therapist can readily incorporate exposure treatments into their range of options with traumatized clients and patients.
Literature Review On Exposure Therapy In PTSD
Solomon, Gerrity, and Muff (12) reviewed the psychological treatment outcome literature in PTSD finding essentially five projects that met their criteria of random assignment to condition, pre- and posttest evaluation, and the presence of a comparison group. They concluded that exposure therapies held the most initial promise among the treatments that had been examined empirically. A study by our group (e.g., 13) indicated that exposure therapy was particularly effective for approximately two-thirds of the subjects in the trial resulting in systematic symptom reductions across a wide range of intrusive and arousal types of symptoms. That study did not find changes in the avoidant/numbing symptoms, findings that may be a function of the assessment instruments we used or the limitations of the technique. Further studies with superior dependent variables such as the Clinicians Administered PTSD Scale (14-15) will help determine the extent to which these preliminary findings are robust.
Subsequent studies were designed to replicate and extend these findings. Cooper and Clum (16) and Boudewyns and Hyer (17) also found that those who received exposure therapy embedded in a more comprehensive treatment program experienced greater reductions in PTSD symptoms than those who did not receive the exposure therapy. These studies were also conducted with combat veterans.
Moreover, Foa, Rothbaum, Riggs, & Murdoch (18) demonstrated that among women with rape-related PTSD, those subjects who received exposure based treatment showed continued improvement following post-treatment assessments. These subjects psychological condition was superior to that of the subjects receiving stress inoculation treatment at a three month follow-up.
Other studies contribute to the conclusion that the use of an exposure component in the treatment of PTSD has beneficial effects above and beyond what is offered in traditional treatment approaches. In the only controlled study conducted outside the United States, Brom, Kleber, and Defares (19) demonstrated that systematic desensitization was as effective as other approaches in the treatment of PTSD secondary to multiple types of traumatic events. To date, issues of culture, ethnicity, and race have received little attention in the PTSD treatment literature, largely due to the relatively small sample sizes employed in existing studies.
Clearly, the numerous single-subject design studies (e.g., 20-28), coupled with the more methodologically strong randomized studies reviewed above, indicate that exposure treatment is effective in the alleviation of traumatic symptomatology. The questions for the clinician, then, are with which patients is exposure therapy most effective, for what kinds of symptoms, and at what point in therapy should exposure treatment occur? Unfortunately there are few data to guide the clinician in making these decisions. Consequently, the remainder of this article will attempt to provide the reader with guidelines developed through clinical experience.
Phase Oriented Treatment Of PTSD
PTSD patients' symptom patterns are phasic in nature (29-30) with periods characterized by intrusive or reliving experiences alternating with periods of avoidance and numbing symptoms. Sometimes these periods are overlapping and at times they are sequential, lasting variable lengths of time. When patients are experiencing an exacerbation of their condition it is usually in response to current stressors or to exposure to cues reminiscent of the traumatic event. These periods of exacerbation often involve destabilization in the lives of patients and considerable psychological and social disorganization. There is frequently an accompanying problem of substance abuse.
A period of crisis drives many patients into therapy and this is clearly not the time to conduct any form of exposure treatment. Initial efforts are best directed at crisis resolution, stabilization, and modification of substance use. Until there is some degree of stability in the life of the patient it is unwise to begin any form of intensive therapy. This is the Emotional and Behavioral Stabilization Phase of our multiphasic approach to PTSD treatment (31).
The second phase of treatment is centered upon teaching the patients about their disorder, the effects of chronic PTSD, implications for their interpersonal relations and response to ordinary stressors, and the course of disorder. This Trauma Education Phase is marked by an emphasis on providing a fundamental understanding of the ramifications for people who are exposed to life-threatening, traumatic events and who develop PTSD.
Phase three emphasizes the teaching of specific skills to assist individuals to manage their anxiety, stress, and response to interpersonal stressors. Relaxation training, interpersonal skills training, anger management training, and problem solving treatments comprise the primary skills taught to patients. Collectively these skills are described as the Stress Management Phase. These skills, once mastered, are important for use outside the therapy setting, but will also be critical in instilling in the patient a sense of efficacy about managing stressors. This will be invaluable as patients enter the next phase of treatment wherein the focus changes from skill acquisition to emotional processing of the traumatic event and its sequelae. As work in therapy shifts to the traumatic event patients can utilize their newly developed stress management skills to help them manage the stress that will be evoked.
Trauma Focus Phase of treatment occurs when the patient has mastered the necessary skills so that they feel more prepared for intensive, direct intervention regarding their traumatic event. It is in this phase where exposure therapies are employed. This treatment component can be systematic desensitization, flooding, implosive therapy, or any of the variants described above. These options are seen as preferable for the processing of a traumatic event, compared with insight or talk therapies, largely because they incorporate behavioral, physiological, and cognitive cues, providing more complete access to the complex of factors thought to be involved in processing human emotion (32-34).
Foa and Kozak's (35) convincing extrapolation from the bioinformational theory of Lang (32) posits that these exposure-based procedures optimize the patient's capacity to access all dimensions of the traumatic memory network, provide a corrective therapeutic experience, permit a reduction in emotional valence through extinction processes, which then promotes a cascade of adaptive cognitive processes to occur, such as challenging of irrational beliefs, crippling attitudes, and dysfunctional values. If there are multiple traumatic events, each traumatic memory can be treated sequentially and with input from the patient as to the preferred order that each will be addressed.
As therapy proceeds, patients need to be equipped for the inevitable recurrence of symptomatology. Stressors that are related or even unrelated to the traumatic events in question can trigger a return of traumatic symptomatology. In the Relapse Prevention Phase of treatment the patient is instructed how to best manage and master the return of symptoms. Efforts to mobilize social support systems and to promote the use of stress management skills when stressors occur will extend the effects of the more intensive phases of therapy.
Since many patients in public sector treatment facilities evidence chronic disorder, it is valuable to incorporate an additional component of treatment. Follow-up and Maintenance Phase of treatment for PTSD includes the development of the expectation that the therapist is available as a consultant as the need may arise. For some patients the use of self-help groups may provide the necessary structure for promoting adaptive change and the maintenance of treatment gains. Booster sessions can be scheduled to provide specific points of access to support by the therapist and treatment sessions can be systematically phased-out over an extended time.
This six phase approach to treating PTSD provides a heuristic framework for interventions geared to the adult PTSD patient (Table 1). While it is recognized that the treatment of PTSD cannot be easily
-----
Table 1. Six-Phase Oriented Treatment Of PTSD
1. Emotional and behavioral stablization phase
2. Trauma Education phase
3. Stress Management phase
4. Trauma Focus phase
5. Relapse Prevention phase
6. Follow-up and Maintenance phase
------
compartmentalized and that at times patients require extended periods within a single phase before advancing to the next phase, this method does provide the clinician with both long-and short-term strategies and specific goals for managing PTSD patients.
Treatment Caveats
Our phase oriented approach to treating PTSD assumes that patients are ready and prepared to proceed from one phase to another. Clinical judgment in concert with patient input are the determinants of whether an individual is, in fact, ready to proceed to the next phase. Some patients will require longer amounts of time in one stage or another depending upon their clinical condition. For other patients, it may be necessary to return to earlier phases if their clinical status demands additional time to master their objectives of that phase. Clearly the phases that we have proposed are both fluid and dynamic in nature in that the clinician can judge the extent to which an individual needs additional treatment of a certain type. In practice, the clinician works in conjunction with the patient to determine the next steps in the treatment program. Goals and objectives are routinely discussed and modified on the basis of the progress experienced.
Clinicians who are trained in exposure methods for treating other forms of psychopathology will find the need to address several issues when applying these skills to PTSD. First, it is valuable to have a consultant or a supervisor who has experience with this particular patient population. This advisor can provide insights into the process of recovery in traumatized patients. Second, if a patient's life is disrupted either through family crises or other forms of social instability, this is not the time to initiate intensive exposure therapy. Focus should remain on the first phase of therapy with perhaps an extension into the third phase.
Third, if a patient is involved in active substance abuse, the focus should be on containment and stabilization of the patient's condition with the more intensive trauma focus phase being implemented when a period of sobriety has been attained. Recommended lengths of time for sobriety vary, particularly when PTSD is involved, largely due to the fact that many patients abuse substances to ease their traumatic symptomatology (36). For these patients it is preferable to begin the more intensive and direct exposure therapy earlier in the sobriety (e.g. 8-12 weeks). The sooner their therapist can provide relief from the PTSD symptoms, the more likely it is that the patient will remain sober.
There are clearly many variables to be weighed by the clinician in these situations and no peremptory rules can be developed. In the balance is the therapeutic need to have a stable and sober patient prior to intensive treatment versus some patients' inability to achieve stability and sobriety without relief from their traumatic symptoms. If the clinician waits too long to effectively intervene, the patient may become increasingly hopeless and leave therapy. If the clinician intervenes too early, the patient may not be able to tolerate the stress associated with the processing of their traumatic histories and resort to alcohol abuse or other maladaptive patterns (37).
Fourth, the presence of multiple traumatic events is also a consideration in the use of exposure approaches to treatment. Previous studies from our group indicated that patients with memories of four to six traumatic events can be successfully treated using exposure. Each memory is considered an independent entity and hierarchies are developed accordingly. However, for some people, particularly those who have experienced war, the number of traumatic events to which they have been exposed can conceivably be dozens. While there are no existing studies on this topic, we have chosen to use approaches that emphasize containment in such instances (e.g. supportive counseling, education, stress management, skills training, etc.).
A fifth caveat in the use of exposure treatments is the presence of complicating medical and psychiatric comorbidity. Patients with cardiovascular disease including angina, a history of myocardial infarction, and severe hypertension might well be ruled out as candidates for any evocative or intensive therapy. In addition, patients with poor cognitive functioning, psychotic thought processes, or with impulse control problems (i.e., actively suicidal or homicidal) would not be good candidates until their conditions were stabilized. As with all therapies, patient noncompliance with therapist instruction would also preclude the use of exposure therapy. A good therapeutic alliance is an important consideration. For further discussion on this topic, Litz, Blake, Gerardi, and Keane (38) have proposed additional guidelines for the use of exposure therapy in the treatment of PTSD.
Summary. Exposure therapies are empirically documented, effective treatments for PTSD. Efficacy studies with war veterans, rape victims, and survivors of a broad array of traumatic events demonstrate that this form of treatment is a valuable addition to a therapist's clinical skills. When utilized with a comprehensive treatment program that addresses the psychological, social, and physiological elements of the disorder, exposure therapies offer innovative methods for addressing the symptoms of PTSD and for alleviating the residual emotions, distress, and physiological reactions to specific traumatic events. Future research is necessary to further document the effectiveness of treatments for PTSD and data are needed to substantiate the efficacy of the phase-oriented treatment program described in this article.
References
1. Chemtob, C.M., Roitblat, H.L., Hamada, R.S., Carlson, J.G., & Twentyman, C.T. (1988). A cognitive action theory of posttraumatic stress disorder. Journal of Anxiety Disorders, 2, 253-275.
2. Foa, E. B., Steketee, G., & Rothbaum, B.O. (1989). Behavioral/cognitive conceptualizations of post-traumatic stress disorder. Behavior Therapy, 20, 155-176.
3. Keane, T.M., Zimering, R.T., & Caddell, J.M. (1985). A behavioral formulation of post-traumatic stress disorder in combat veterans. The Behavior Therapist, 8, 9-12.
4. Wolpe, J. (1958). Psychotherapy by reciprocal inhibition. Stanford, California: Stanford University Press.
5. Rachman, S. (1966). Studies in desensitization-II: Flooding. Behavior Research and Therapy, 4, 1-6.
6. Stampfl, T.G. & Levis, D.J. (1967). Essentials of implosive therapy: A learning-theory-based psychodynamic behavioral therapy. Journal of Abnormal Psychology, 72, 496-503.
7. Bandura, A. (1969). Principles of behavior modification. New York: Holt.
8. Cautela, J.R. (1971). Covert extinction. Behavior Therapy, 2, 192-200.
9. Shapiro, F. (1995). Eye movement desensitization and reprocessing. New York: Guilford.
10. Lyons, J.A. & Keane, T.M. (1989). Implosive therapy in the treatment of combat related PTSD. Journal of Traumatic Stress, 2, 137-152.
11. Vaughan, K. & Tarrier, N. (1992). The use of image habituation training with posttraumatic stress disorders. British Journal of Psychiatry, 161, 658-661.
12. Solomon, S.D., Gerrity, E.T., & Muff, A.M. (1992). Efficacy of treatments of posttraumatic stress disorder. Journal of the American Medical Association, 268, 633-638
13. Keane, T.M., Fairbank, J.A., Caddell, J.M. & Zimering, R.T. (1989). Impressive (flooding) therapy reduces symptoms of PTSD in Vietnam combat veterans. Behavior Therapy, 20, 345-260.
14. Blake, D. D., Weathers, F.W., Nagy, L.N., Kaloupek, D. G., Klauminzer, G., Charney, D.S., & Keane, T.M. (1990). A clinician rating scale for assessing current and lifetime PTSD: The CAPS-1. The Behavior Therapist, 13, 187-188.
15. Weathers, F.W. & Litz, B.T. (1994) Psychometric properties of the Clinician-Administered PTSD Scale, CAPS-1. PTSD Research Quarterly, 5, 2-6.
16. Cooper, N.A. & Clum, G.A. (1989). Imaginal flooding as a supplementary treatment for PTSD in combat veterans: A controlled study. Behavior Therapy, 20, 381-391.
17. Boudewyns, P.A. & Hyer, L. (1990). Physiological response to combat memories and preliminary treatment outcome in Vietnam veteran PTSD patients treated with direct therapeutic exposure. Behavior Therapy, 21, 63-87.
18. Foa, E.B., Rothbaum, B.O., Riggs, D.S., & Murdock, T.B. (1991). Treatment of posttraumatic stress disorder in rape victims: A comparison between cognitive-behavioral procedures and counseling. Journal of Consulting and Clinical Psychology, 59, 715-723.
19. Brom, D., Kleber, R.J., & Defares, P.B. (1989). Brief psychotherapy for posttraumatic stress disorders. Journal of Consulting and Clinical Psychology, 57, 607-612.
20. Black, J.L. & Keane, T.M. (1982). Implosive therapy in the treatment of combat related fears in a World War II Veteran. Journal of Behavior Therapy and Experimental Psychiatry, 13, 163-165.
21. Fairbank, J.A., Gross, R.T., & Keane, T.M. (1983). Treatment of post-traumatic stress disorder: Evaluating outcome with a behavioral code. Behavior Modification, 7, 577-568.
22. Fairbank, J.A. & Keane, T.M. (1982). Flooding for combat-related stress disorders: Assessment of anxiety reduction across traumatic memories. Behavior Therapy, 13, 499-510.
23. McCaffrey, R.J. & Fairbank, J.A. (1985). Behavioral assessment and treatment of accident-related posttraumatic stress disorder: Two case studies. Behavior Therapy, 16, 406-416.
24. Nishith, P., Hearst, D.E., Mueser, K.T., & Foa, E.B. (1995). PTSD and major depression: Methodological and treatment considerations in a single case design. Behavior Therapy, 26, 319-335.
25. Keane, T.M. & Kaloupek, D.G. (1982). Imaginal flooding in the treatment of a posttraumatic stress disorder. Journal of Consulting and Clinical Psychology, 50, 138-140.
26. Mueser, K.T., Yarnold, P.R., & Foy, D.W. (1991). Statistical analysis for single-case designs: Evaluating outcome of imaginal exposure treatment of chronic PTSD. Behavior Modification, 15, 134-155.
27. Rychtarik, R.G., Silverman, W.K., Van Landingham, W.P., & Prue, D.M. (1984). Treatment of an incest victim with implosive therapy: A case study. Behavior Therapy, 15, 410-420.
28. Saigh, P.A. (1989). The use of an in vitro flooding package in the treatment of traumatized adolescents. Developmental and Behavioral Pediatrics, 10, 17-21.
29. Horovitz, M.J. (1986). Stress-response syndromes: A review of posttraumatic and adjustment disorders. Hospital and Community Psychiatry, 137, 241-249.
30. Keane, T.M. (1989). Post-traumatic stress disorder: Current status and future directions. Behavior Therapy, 20, 149-153.
31. Keane, T.M., Fisher, L.M., Krinsley, K.E., & Niles, B.L. (1994). Posttraumatic stress disorder. In M. Hersen & R.T. Ammerman (Eds.), Handbook of prescriptive treatments for adults (pp. 237-260). New York: Plenum.
32. Lang, P.J. (1977). Imagery in therapy: An information processing analysis of fear. Behavior Therapy, 8, 862-886.
33. Lang, P.J. (1995). The emotion probe. American Psychologist, 50, 37-385.
34. Lazarus, R.S. (1991). Progress on a cognitive-motivational-relational theory of emotion. American Psychologist, 46, 819-834.
35. Foa, E. B. & Kozak, M.J. (1986). Emotional processing of fear: Exposure to corrective information. Psychological Bulletin, 99, 20-35.
36. Keane, T.M., Gerardi. R.J., Lyons, J.A., & Wolfe, J. (1988). The interrelationship of substance abuse and PTSD: Epidemiological and clinical considerations. In M. Galanter (Ed.). Recent developments in alcoholism Vol. 6. New York: Plenum.
37. Pitman, R.K., Altman, B., Greenwald, E., Longpre, R.E., Macklin, M.L., Poire, R.E., & & Steketee, G.S. (1991). Psychiatric complications during flooding therapy for posttraumatic stress disorder. Journal of Clinical Psychiatry, 52, 17-20.
38. Litz, B.T., Blake, D.D., Gerardi, R.G., & Keane, T.M. (1990). Decision making guidelines for the use of direct therapeutic exposure in the treatment of post-traumatic stress disorder. The Behavior Therapist, 13, 91-93.
Terence M. Keane is Chief of the Psychology Service at the Boston VA Medical Center and Professor of Psychiatry at Tufts University School of Medicine. Director of the National Center for PTSD's Behavioral Science Division, Dr. Keane was among the original group of clinicians who extended the rich literature on experimental clinical psychology to PTSD. A practitioner of cognitive-behavior therapy, he remains active in research, teaching, clinical service, and health care administration.
|
