Dr. Hembree is assistant professor of psychology at the University of Pennsylvania Center for the Treatment and Study of Anxiety in Philadelphia.
Acknowledgments: Preparation of this manuscript was supported by National Institute of Mental Health Grant #MH42178.
This article provides a brief summary of theory underlying trauma-focused psychotherapy for posttraumatic stress disorder (PTSD), with emphasis on emotional processing theory and cognitive theory. Psychosocial approaches to the treatment of PTSD that have received the strongest empirical support are cognitive-behavioral interventions, including prolonged exposure therapy, cognitive therapy, and stress-inoculation training. Eye movement desensitization and reprocessing has also received empirical support. Each of these treatment interventions is described and selected controlled studies supporting their efficacy are reviewed.
Among the psychosocial approaches to the treatment of posttraumatic stress disorder (PTSD), cognitive-behavioral interventions have been the most widely studied and have received strong empirical support. Experts have frequently recommended cognitive-behavioral treatment (CBT) as a first-line intervention for chronic PTSD.1 Accordingly, the psychosocial treatments discussed in this article are limited to CBT approaches and include exposure therapy, cognitive therapy, stress-inoculation training (SIT), and eye movement desensitization and reprocessing (EMDR). Each of these treatment interventions will be described and selected controlled studies supporting their efficacy will be reviewed.
These empirically supported approaches to the treatment of chronic PTSD, although differing in methods of intervention, are similar in their conceptualizations of the impact of trauma and in their objectives for alleviating the resulting sequelae. Thus, a brief summary of the theoretical base of current trauma-focused therapies is provided, with particular emphasis on emotional processing theory2,3 and cognitive theory.4-6
According to Foa and colleagues,7,8 the presence of PTSD reflects impairment in the emotional processing of a traumatic event, resulting in the formation of a trauma memory containing elements of pathological fear. In their treatise on emotional processing theory, Foa and Kozak2 described the pathological fear that is characteristic of anxiety disorders as disruptively intense, resistant to modification, and associated with unrealistic elements and excessive responses. Foa and Kozak2 suggested that treatment must correct the pathological elements of the fear memory by activating or accessing that memory and providing new information that is incompatible with the existing pathological or unrealistic elements.
According to the emotional processing theory of PTSD, the common tactic of avoiding trauma-related memories and cues interferes with the processing of the traumatic event and natural recovery. Avoidance helps in the short-term by reducing anxiety, but also maintains trauma-related symptoms by preventing the survivor from emotionally processing, organizing, and integrating the traumatic experience. The erroneous cognitions and irrational fear associated with the trauma memory are also maintained.
Indeed, most current theories of PTSD emphasize the important role of pathological cognitions in the development and persistence of posttrauma sequelae.4,8 Foa and colleagues8 suggested that a trauma memory associated with PTSD is distinguished from a normal trauma memory by the presence of pathological stimuli associations as well as inaccurate evaluations of danger (eg, a woman assaulted by a bearded man while out late one evening begins to associate assault with bearded men and nighttime. Thus, she believes that bearded men and being out after dark are dangerous).
Ehlers and Clark4 emphasized that individuals with persistent PTSD view the traumatic event and associated information as currently threatening, and thus experience an enduring sense of danger. In their view, one of the core cognitive distortions underlying PTSD is the interpretation of the reexperiencing symptoms of PTSD as currently threatening.
When PTSD was first classified as an anxiety disorder in the Diagnostic and Statistical Manual of Mental Disorders, Third Edition9 it was viewed by cognitive-behavioral clinicians as a complex phobia best conceptualized within the conditioning model of fear and avoidance. This led some researchers to employ exposure procedures that had been found successful with phobias. Participants in these early exposure therapy studies were most commonly male Vietnam veterans.10 Simultaneously, the observation that PTSD patients exhibit symptoms of general anxiety led other researchers to employ anxiety management programs for PTSD (eg, SIT).11,12 Participants in these programs were often female (sexual and nonsexual) assault victims. More recent outcome studies for PTSD have examined the efficacy of cognitive therapy, combinations of exposure and cognitive therapy, and EMDR. Recent studies have also included patients with traumatic experiences other than combat or violent assault in adulthood (eg, motor vehicle accidents, natural disasters, and childhood sexual abuse).
The long-standing notion that psychotherapeutic treatment of trauma should include some form of disclosure or confrontation with the traumatic event13 is central to exposure therapy for PTSD. In exposure therapy, patients are encouraged to confront the feared and avoided memories and situations via two main procedures: imaginal and in vivo exposure.
In imaginal exposure (ie, trauma recounting), the patient is asked to vividly imagine the traumatic event and describe it aloud, along with the thoughts and feelings that occurred during the event. In vivo exposure involves systematic and gradual confrontation with safe but avoided situations, places, or activities that will trigger trauma-related fear and anxiety. In both imaginal and in vivo exposure procedures, the aim is to have the patient engage in the exposure repeatedly and remain in contact with the anxiety-provoking memory or situation until their anxiety declines (ie, habituates) significantly.
One example is a woman who was struck at high speed by another car after 25 years of driving without any serious incidents. Her physical injuries healed well, but she had frequent nightmares about the trauma and became quite fearful of driving or riding in cars. Soon she feared being in public in general and stopped going to work or leaving home unless absolutely necessary. This avoidance reduced her distress in the short-term but also maintained her fear by preventing her from learning that she could safely ride in or drive cars again. Avoidance also prevented her from achieving a realistic perspective about the traumatic event. During exposure therapy, the woman was asked to repeatedly recall the memory of the accident and recount what happened during and in the immediate aftermath of it. While initially feeling anxious and distressed as she repeatedly relived the memory of this accident, her anxiety decreased as she learned that it was not dangerous to think or talk about the accident and that doing so helped her make sense of what happened. Similarly, the woman was asked to engage in in vivo exposure by gradually confronting the situations she had been avoiding, such as riding in cars, driving, and being in public places.
As in imaginal exposure, this confrontation with safe or low-risk yet avoided situations typically causes an initial increase in anxiety and distress, which declines with repeated practice. These confrontations with traumatic memories and external cues provide opportunities for corrective information to be integrated into the trauma memory, thus lessening the fear associated with it.
How does exposure to trauma memories and cues help to modify trauma-related cognitions? How does exposure lead to improvement in PTSD?
First, discussing and recounting the traumatic event with a supportive and knowledgeable therapist helps the patient realize that thinking about the trauma is not dangerous. Second, repeated imaginal reliving of the trauma and in vivo exposure facilitates reduction of the anxiety associated with the trauma memory. The patient learns that anxiety itself is not dangerous and will eventually decrease without avoidance or escape. Third, focusing on the trauma memory and engaging in in vivo exposure decreases the generalization of fear and avoidance by helping the patient differentiate the traumatic event from other situations. Rather than viewing the entire world as dangerous, the patient comes to realize that the traumatic event was an isolated incident. Fourth, confronting rather than avoiding trauma-related fears and memories helps change the PTSD sufferer’s view that their symptoms mean they are incompetent and weak. Exposure facilitates the development of a strong sense of mastery and counters the victim’s self-perception as incompetent.
Stress Inoculation Training
Anxiety management approaches were commonly utilized in early research on female rape and crime victims. One such approach is SIT,11 which provides coping skills or techniques that the patient can use to manage and reduce anxiety as it occurs. Veronen and Kilpatrick12 adapted Meichenbaum’s SIT program specifically for use with female assault survivors. They posited that during a traumatic event, emotional, cognitive, and behavioral fear responses are evoked by the experience or threat of physical injury, pain, or death. These responses are mediated by cognitive appraisal and attribution.
Through classical conditioning, neutral stimuli (eg, places, people, hair color, time of day) become associated with trauma-related unconditioned stimuli (eg, weapons, pain, injury) and acquire the potential to trigger fear and anxiety. These neutral situations are subsequently avoided or escaped in order to decrease the anxiety they provoke. In turn, the resulting reduction in anxiety reinforces these avoidance responses. For example, a man who is robbed at gunpoint while working in a convenience store develops a fear of customers with the same physical characteristics as the robber, working the shift he was working when the robbery occurred, and shopping in any convenience store himself. Eventually the fear causes the victim to stop working and to avoid contact with others.
An adaptation of SIT was designed by Veronen and Kilpatrick12 to teach rape survivors skills that they can use to manage and decrease rape-related fear and anxiety. Components included education about trauma and PTSD, deep muscle relaxation, breathing exercises, cognitive restructuring (CR), covert modeling, role playing, thought stopping, and guided self-dialogue. Importantly, they explicitly instructed patients to use these skills when confronting situations or activities that triggered rape-related anxiety and fear.
Cognitive theory holds that it is the interpretation of events, rather than events themselves, that lead to specific emotional responses.14,15 Thus, as frequently happens in individuals with PTSD, when benign events are interpreted as threatening, negative emotions such as anxiety, depression, anger, or guilt emerge. The primary goals of cognitive therapy for PTSD are to teach the patient to identify irrational or unhelpful trauma-related beliefs that might influence their interpretation of a situation and lead to intense negative emotion, and to learn to challenge these thoughts or beliefs in a nonemotional, evidence-based manner. In challenging the trauma-related belief or thought, relevant facts that support or do not support the belief are examined and alternative ways of interpreting the elicited situation are considered. The patient learns to weigh the evidence and alternative explanations and subsequently decide whether the belief is helpful and accurately reflects reality. If it does not, the patient generates a modified or more accurate belief to replace it.
Resick and Schnicke16,17 developed the cognitive-processing therapy (CPT) program to specifically address the concerns and symptoms of rape victims with chronic PTSD. This treatment approach is based on the assumption that PTSD results from conflicts between the new information conveyed by a traumatic event and prior schema about the world and the self. Thus, the focus of treatment in CPT is on identifying and modifying these conflicts, termed “stuck points.”17 CPT also focuses on themes typically related to the trauma of rape (eg, safety, trust, power, esteem, and intimacy).6 A written exposure component is designed to encourage expression of affect and to ensure that all the important trauma-related feelings and associated beliefs are elicited.
EMDR is a more recent therapeutic approach18,19 that has generated interest among trauma therapists and researchers. In EMDR for PTSD, the therapist asks the patient to generate images, thoughts, and feelings about the trauma, to evaluate their affective qualities, and to make alternative cognitive appraisals of the trauma or their behavior during it. At various points in the session (when the patient focuses on the distressing images and thoughts or on the alternative cognition), the therapist elicits rapid saccadic eye movements by instructing patients to visually track a finger rapidly waved back and forth in front of their faces.
Originally, Shapiro18 regarded the saccadic eye movements as essential to the processing of the traumatic memory and proposed that the eye movements in some way override or reverse the neural blockage induced by the traumatic event. However, the assertion that the rapid eye movements play an essential role in treatment response has not been supported by dismantling studies.20-22
Treatment Outcome Studies
This section briefly presents results from selected controlled studies of the interventions described above. For comprehensive reviews, see Foa and Rothbaum23 or Rothbaum and colleagues.24
Many well-controlled studies have found exposure therapy to be an effective treatment in reducing PTSD and related pathology such as depression and anxiety. Exposure therapy has shown efficacy in men with combat-related PTSD12,25 and women with assault-related PTSD,26-28 although overall, the latter group shows relatively greater benefit. Working with assault survivors with chronic PTSD, Foa and colleagues27 compared the effects of manualized exposure therapy (prolonged exposure [PE]), SIT, and the combination of PE and SIT (PE/SIT) to a waitlist control group. They found that women treated with either treatment alone or with PE/SIT showed a reduction in PTSD severity and depression, whereas the waitlist group did not show any improvement. Furthermore, exposure alone (PE) was superior to SIT and PE/SIT on several indices of treatment outcome.
In a subsequent study of female assault victims with chronic PTSD, Foa and colleagues29 found that 9 or 12 sessions (determined by rate of improvement in self-reported PTSD symptoms) of exposure alone and exposure with CR effected a large and equal improvement in PTSD and depression symptoms. However, exposure alone emerged as a more efficient program compared to exposure plus CR. Significantly more women in the exposure-alone condition than in the combined condition were able to end therapy at nine sessions by meeting the success criterion of at least 70% improvement in PTSD symptoms.
Resick and Schnicke16 used CPT to treat groups of rape victims. They reported significantly greater reduction in PTSD symptoms and depression following CPT compared to a naturally-occurring waitlist control group. Resick and colleagues28 have recently conducted a large study comparing the efficacy of 12 sessions of individually administered CPT to 9 sessions of PE for rape victims with PTSD. Preliminary results based on 45 participants indicated that both treatments are highly and equally effective.
The generalizability of the findings by Resick and colleagues is strengthened by recent investigations of CBT conducted with individuals in whom PTSD resulted from a variety of traumatic events, including motor vehicle accidents, disasters, and childhood sexual abuse and criminal victimization. Most have produced results similar to those found with female assault victims.
Marks and colleagues30 treated mixed-trauma patients who had chronic PTSD with either exposure alone, CR alone, combined exposure and CR, or relaxation training. They found that exposure, CR, and the combination of exposure and CR were equally effective and were superior to relaxation. Tarrier and colleagues31 compared imaginal exposure (without in vivo) to cognitive therapy in a sample of patients with PTSD mostly due to criminal victimization or motor vehicle accidents. Exposure and cognitive therapies were found to be significantly and equally effective at ameliorating PTSD severity. Echeburua and colleagues32 found that gradual exposure with CR produced more improvement in PTSD, fear, and depression than relaxation training, and this difference was maintained through the 12-month follow-up assessment.
The efficacy of EMDR has been assessed in a number of studies, although many were not well controlled. Generally, outcome studies show that EMDR is effective at reducing PTSD symptoms relative to waitlist controls. In a small but well-controlled study of EMDR for rape victims with PTSD, Rothbaum33 found that 90% of patients receiving four sessions of EMDR (compared to 12% of waitlist patients) no longer met criteria for PTSD, and gains were maintained at 3-month follow-up.
In a similar but much larger study (80 trauma victims, only 46% of whom met criteria for PTSD) using self-report measures, Wilson and colleagues34 also found that three sessions of EMDR significantly reduced PTSD severity, anxiety, and general distress compared to waitlist controls, and treatment gains were maintained at 15-month follow-up.35
Devilly and Spence36 conducted the only published study to date that compared EMDR to a treatment of established efficacy for PTSD, although several more are nearing publication. Patients with PTSD were treated with nine sessions of either EMDR or a CBT package consisting of prolonged imaginal and in vivo exposure, SIT, and cognitive therapy. As assessed by self-report measures, CBT patients showed significantly greater improvement in PTSD than did EMDR patients at both posttreatment and follow-up. Individuals treated with CBT maintained their treatment gains at the follow-up assessment, while individuals treated with EMDR showed relapse on several measures. In addition, EMDR and CBT were rated as equally (“moderately”) distressing and CBT was rated as more credible and generated higher expectancies for change.
Many studies have indicated that prolonged exposure therapy is an effective and efficient treatment for PTSD resulting from a variety of traumas. SIT has been found effective, but the evidence comes exclusively from studies on female assault victims and the generalizability of the results to other populations is unknown. Although relatively fewer studies have been conducted on the efficacy of cognitive therapy for PTSD as compared to exposure therapy, the results indicate that CR and CPT are quite effective. EMDR appears promising, but more well-controlled studies are needed for a firm conclusion. EMDR dismantling studies are fairly consistent in finding that the eye movements and variations on these (flashing lights, finger tapping) are irrelevant to outcome. This has led some to conclude that treatment effects are likely to be nonspecific or due to the imaginal exposure generated by the procedure.37
Research on psychosocial treatments for chronic PTSD has clearly demonstrated the efficacy of several CBTs in ameliorating PTSD symptoms, depression, and anxiety. Comparative studies have generally found equivalence in outcome among exposure, cognitive therapy, stress inoculation, and combinations of these interventions. Follow-up evaluations ranging from 3–12 months in the CBT outcome studies indicate that treatment gains are maintained and, in some cases, even increased relative to their level at posttreatment. This is especially true for treatments that include exposure, either alone or in combination. Treatment dropout rates for CBT are relatively low, averaging 14% in 27 psychotherapy studies analyzed in a recent meta-analysis of PTSD treatment outcome trials.38 Thus, it appears that the treatments are generally well tolerated.
Foa and Rothbaum23 suggested that, irrespective of the treatment modality utilized, successful psychotherapy for PTSD must produce changes in the patient’s inaccurate beliefs about the world and him/herself. This view is substantiated by the consistent results of many outcome studies. Although the psychotherapeutic approaches discussed in this article employ different interventions and procedures, they share the common goal of helping the trauma survivor integrate and make sense of the traumatic event while managing significant anxiety. It remains the task of future research efforts to determine if the treatment benefits realized by prolonged exposure therapy are indeed relatively more enduring and efficient. PP
1. Foa EB, Davidson JRT, Frances A. The Expert Consensus Guidelines Series: treatment of posttraumatic stress disorder. J Clin Psychiatry. 1999;60:4-76.
2. Foa EB, Kozak MJ. Emotional processing of fear: exposure to corrective information. Psychol Bull. 1986;99:20-35.
3. Foa EB. Psychological processes related to recovery from a trauma and an effective treatment for PTSD. In: Yehuda R, McFarlane A, eds. Psychobiology of PTSD. New York, NY: New York Academy of Science; 1997:410-424.
4. Ehlers A, Clark DM. A cognitive model of posttraumatic stress disorder. Behav Res Ther. 2000;38:319-345.
5. Janoff-Bulman R. Shattered Assumptions: Towards a New Psychology of Trauma. New York, NY: Free Press; 1992.
6. McCann IL, Pearlman LA. Psychological Trauma and the Adult Survivor: Theory, Therapy, and Transformation. New York, NY: Bruner/Mazel; 1990.
7. Foa EB, Jaycox LH. Cognitive-behavioral theory and treatment of posttraumatic stress disorder. In: Spiegel D, ed. Efficacy and Cost-Effectiveness of Psychotherapy. Washington, DC: American Psychiatric Press; 1999:23-61.
8. Foa EB, Steketee G, Rothbaum B. Behavioral/cognitive conceptualizations of post-traumatic stress disorder. Behav Ther. 1989;20:155-176.
9. Diagnostic and Statistical Manual of Mental Disorders. 2nd ed. Washington, DC: American Psychiatric Association; 1980.
10. Keane TM, Fairbank JA, Caddell JM, Zimering RT. Implosive (flooding) therapy reduces symptoms of PTSD in Vietnam combat veterans. Behav Ther. 1989;20:245-260.
11. Meichenbaum D. Self-instructional methods. In: Kanfer FH, Goldstein AP, eds. Helping People Change. New York, NY: Pergamon; 1975:357-391.
12. Veronen LJ, Kilpatrick DG. Stress management for rape victims. In: Meichenbaum D, Jaremko ME, eds. Stress Reduction and Prevention. 1983:341-374.
13. Fenichel O. The concept of trauma in contemporary psycho-analytical theory. Int J Psychoanal. 1946;26:33-44.
14. Beck AT. Cognitive Therapy and the Emotional Disorders. New York, NY: International University Press; 1976.
15. Beck AT, Emery G, Greenberg RL. Anxiety Disorders and Phobias: A Cognitive Perspective. New York, NY: Basic Books; 1985.
16. Resick PA, Schnicke MK. Cognitive processing therapy for sexual assault victims. J Consult Clin Psychol. 1992;60:748-756.
17. Resick PA, Schnicke MK. Cognitive Processing Therapy for Rape Victims: A Treatment Manual. Newbury Park, Calif: Sage; 1993.
18. Shapiro F. Eye movement desensitization and reprocessing procedure: from EMD to EMD/R-A, new treatment model for anxiety and related trauma. Behav Ther. 1991;5:128-133.
19. Shapiro F. Eye Movement Desensitization and Reprocessing: Basic Principles, Protocols, and Procedures. New York, NY: Guilford Press; 1995.
20. Pitman RK, Orr SP, Altman B, Longpre RE, Poire RE, Macklin ML. Emotional processing during eye movement desensitization and reprocessing therapy of Vietnam veterans with chronic posttraumatic stress disorder. Compr Psychiatry. 1996;37:419-429.
21. Renfrey G, Spates CR. Eye movement desensitization: a partial dismantling study. J Behav Ther Exp Psychiatry. 1994;25:231-239.
22. Bauman W, Melnyk WT. A controlled comparison of eye movements and finger tapping in the treatment of test anxiety. J Behav Ther Exp Psychiatry. 1994;25:29-33.
23. Foa EB, Rothbaum BO. Treating the Trauma of Rape. New York, NY: Guilford Publications, Inc; 1998.
24. Rothbaum BO, Meadows EA, Resick P, Foy DW. Cognitive-behavioral therapy. In: Foa EB, Keane TM, Friedman MJ, eds. Effective Treatments for PTSD. New York, NY: Guilford Press; 2000.
25. Cooper NA, Clum GA. Imaginal flooding as a supplementary treatment for PTSD in combat veterans: a controlled study. Behav Ther. 1989;20:381-391.
26. Foa EB, Rothbaum BO, Riggs DS, Murdock TB. Treatment of posttraumatic stress disorder in rape victims: a comparison between cognitive-behavioral procedures and counseling. J Consult Clin Psychol. 1991;59:715-723.
27. Foa EB, Dancu CV, Hembree EA, Jaycox LH, Meadows EA, Street GP. A comparison of exposure therapy, stress inoculation training, and their combination for reducing posttraumatic stress disorder in female assault victims. J Consult Clin Pychol. 1999;67:194-200.
28. Resick PA, Nishith P, Weaver T. Preliminary findings of a controlled trial comparing cognitive processing therapy and prolonged exposure. Paper presented at: 6th European Conference on Traumatic Stress; June 1999; Istanbul, Turkey.
29. Foa EB. A comparison of prolonged exposure and prolonged exposure plus CR in female assault victims with PTSD: preliminary findings. Paper presented at: World Congress of Cognitive and Behavior Therapy; July 2001; Vancouver, Canada.
30. Marks I, Lovell K, Noshirvani H, Livanou M, Thrasher S. Treatment of posttraumatic stress disorder by exposure and/or cognitive restructuring: a controlled study. Arch Gen Psychiatry. 1998;55:317-325.
31. Tarrier N, Pilgrim H, Sommerfield C, et al. A randomized trial of cognitive therapy and imaginal exposure in the treatment of chronic posttraumatic stress disorder. J Consult Clin Psychol. 1999;67:13-18.
32. Echeburua E, de Corral P, Zubizarreta I, Sarasua B. Psychological treatment of chronic posttraumatic stress disorder in victims of sexual aggression. Behav Modif. 1997;21:433-456.
33. Rothbaum BO. A controlled study of eye movement desensitization and reprocessing in the treatment of posttraumatic stress disorder. Compr Psychiatry. 1997;37:419-429.
34. Wilson SA, Becker LA, Tinker RH. Eye movement desensitization and reprocessing (EMDR) treatment for psychologically traumatized individuals. J Consult Clin Psychol. 1995;63:928-937.
35. Wilson SA, Becker LA, Tinker RH. Fifteen-month follow-up of eye movement desensitization and reprocessing (EMDR) treatment for posttraumatic stress disorder psychological trauma. J Consult Clin Psychol. 1997;65:1047-1056.
36. Devilly GJ, Spence SH. The relative efficacy and treatment distress of EMDR and a cognitive-behavior trauma treatment protocol in the amelioration of posttraumatic stress disorder. J Anxiety Disord. 1999;13:131-157.
37. Lohr JM, Tolin DF, Lilienfeld SO. Efficacy of eye movement desensitization and reprocessing: implications for behavior therapy. Behav Ther. 1998;29:123-156.
38. Van Etten ML, Taylor S. Comparative efficacy of treatments for posttraumatic stress disorder: a meta-analysis. Clin Psychol Psychother. 1998;5:125-144.s