The integration of technology and medicine is creating exciting possibilities for psychiatry and the behavioral sciences. A particularly intriguing one is the marriage of virtual reality technology to established behavioral principles and interventions for the treatment of anxiety disorders in general, and specifically posttraumatic stress disorder. This article will describe the current standard of care as well as discuss these innovations and new pharmacologic studies.
Posttraumatic stress disorder (PTSD) is a type of anxiety disorder consisting of a pattern of symptoms that people may develop in the aftermath of overwhelming events involving threatened death or injury, such as military combat, personal assault, terrorist attack, natural disasters, or motor vehicle accidents. Individuals suffering from the disorder re-experience the traumatic event in a number of ways including nightmares or intrusive thoughts about the trauma. They remain alert to danger in the world, maintaining a hypervigilance to their surroundings, and may experience irritability, difficulty with sleep, or concentration. Individuals with PTSD may attempt to cope using avoidance and numbing and may isolate themselves from friends and family and cease to participate in their usual activities.
Expert treatment guidelines for PTSD were published for the first time in 1999, recommending that cognitive-behavioral treatment with exposure therapy should be the primary therapy for PTSD. Cognitive behavioral treatment for PTSD typically offers skills to cope with the symptoms, including the use of relaxation and breathing techniques and in vivo exposure to help individuals approach situations they have been avoiding. Typical treatments also employ the use of imaginal exposure to help individuals process and metabolize their trauma experiences. During the imaginal exposure, the patient recounts the trauma experience in a detailed manner repeatedly over the course of a number of sessions. Alternatively, the patient may listen to the therapist relating a vivid description of the traumatic event. Studies have demonstrated the effectiveness of exposure in treating Vietnam combat veterans, female victims of sexual assault and mixed trauma populations as well as survivors of terrorism.
Despite the established efficacy of exposure therapy, imaginal exposure presents a predicament for some patients: effective imaginal exposure requires that patients tell their trauma to their therapists, over and over again in a manner which allows them to connect to the emotions of that day; yet avoidance of reminders of the trauma is inherent in PTSD. Hence, most people with PTSD never seek treatment, some who seek treatment refuse to engage in the treatment, and others who express willingness are unable to engage their emotions or senses, retelling an emotionless tale, reflecting their numbness. Such patients often fail to improve. This is consistent with the studies that conclude that failure to engage emotionally predicts a poor treatment outcome.
In recent years, virtual reality (VR) technology has provided a tool to enhance treatment. Computer programs simulate different environments which give the patients the illusion that they have gone inside the 3-D virtual world. The set-up employs the use of a headset which responds to an individual’s head movements so that when he changes his head orientation the scenery changes. Headphones provide auditory accompaniment and often a platform may provide vibrations to increase the feeling of immersion in the environment. Most recently “smell machines” have been added that allow different aromas to be released at the push of a button, in order to engage the olfactory sense. Virtual reality therapy was first applied to the treatment of phobias and numerous studies have documented that it is an effective treatment for fear of heights, fear of flying, claustrophobia, and spider phobia.
Recent developments in virtual reality technologies have opened new vistas for the treatment of PTSD by offering patients who are unable to retell their experiences a computer-generated environment in which to encounter and master their trauma. Over the course of the exposure sessions, the patient progresses through a series of computer-generated sequences that gradually increase in intensity and detail at a pace the patient can tolerate. The virtual world is programmed so that the therapist can control what the patient experiences in the virtual world by touching pre-programmed keys on the keyboard. During the exposure segments, the therapist simultaneously views the virtual environments on a computer monitor, as the patient recounts his experience while viewing the virtual world.
VR graded exposure was first successfully applied in treatment of combat-related PTSD. Dr. Barbara Rothbaum and colleagues conducted VR treatment with a man who had served in Vietnam 26 years earlier and suffered from chronic PTSD and Major Depression. Over the course of treatment sessions, he viewed a progressively detailed jungle scene and Huey helicopter scene accompanied by sound effects. The patient’s clinician-rated level of PTSD dropped by 34% and his self-reported levels of PTSD decreased by 45% and these gains were maintained at six-month follow-up. The success of VR treatment for PTSD was reinforced by a study of 10 Vietnam veterans, who demonstrated a 15% to 67% decrease in PTSD at six-month follow up.
We published the first case report on the use of VR therapy to treat PTSD for individuals who witnessed the World Trade Center (WTC) attacks of September 11, 2001, followed by a pilot study conducted on 10 individuals. The WTC virtual environment was developed to allow for a graded hierarchical exposure to the sensory stimuli in the world. Over the course of the exposure sessions, the patients progress through a series of 11 sequences that gradually increase in intensity from a plane silently flying past the WTC to the entire sequence of events of that day including planes crashing into both buildings and their subsequent collapses accompanied by sounds of explosions and screaming. Patients recount their personal experiences while the events are matched in the virtual environment. Participants in the pilot study included disaster workers, non-disaster relief workers and civilians with varying levels of exposure. After 6 to 14 sessions, patients receiving treatment displayed a mean of 43% reduction in PTSD symptoms, compared to no symptom reduction in a waitlist control group. This improvement was maintained at a 6-month follow-up. Significantly, 5 of the patients had previously been treated with imaginal exposure but continued to meet criteria for PTSD.
The success of this program led to the development of an interior version of the WTC program. This second environment targets individuals who were in the towers on 9/11 and simulates their escape from the building. This program is designed to serve as a prototype for other traumas in which evacuation is necessary, including earthquakes and other natural disasters.
Most recently, the virtual reality technology has been utilized to help returning Iraqi war veterans who are suffering from PTSD. A virtual Iraq environment offers a choice of scenarios to match the veterans’ experiences: patients may view an Iraqi city and marketplace or may ride through a desert in a humvee. Sounds of gunfire, explosions, radios, voices and shouts may be added along with accompanying vibrations and smells of gasoline, burning rubber or spices. These elements enhance the immersion of the patients in the environment while they retell their experiences, thereby facilitating the processing of the trauma. The first case study of an Iraqi War veteran published by Drs. Gerardi, Rothbaum and colleagues showed that a 4-session intervention reduced the patient’s PTSD symptoms by 56%.
Further medical advances may enhance the effects of the virtual reality treatment with the administration of D-Cycloserine (DCS; Seromycin). DCS is an antibiotic that has been used in clinical trials over the last decade as a cognitive enhancer. It is a partial agonist at the N-methyl-D-aspartate (NMDA) receptor which is known to play an essential role in learning and memory.
In one recent study, Rothbaum and colleagues assessed the effect of D-Cycloserine (DCS) on outcome for individuals receiving VR treatment for acrophobia. They found that individuals who took a dose of DCS on the days of their VR exposure showed significantly more improvement and the improvement was evident earlier in treatment as compared to patients who did not take DCS, with 2 sessions being sufficient for the DCS group compared to 6 sessions for the controls. In our program at Weill Medical College, we are currently evaluating the effects of DCS on patients undergoing VR treatment for PTSD following the WTC attacks of 9/11/01 or the events of Iraq War. Treatment is also available for family members of returning Iraqi War veterans.
Finally, propanolol, a beta blocker commonly used to treat cardiac problems, is opening up new possibilities in the treatment of PTSD. Both animal and human studies indicate that memory is enhanced by arousal or adrenergic stimulation and that memory for arousing stimuli is impaired if beta-adrenergic receptors are blocked during the time at which the memory is formed or consolidated. Dr. Margaret Altemus at Weill Medical College of Cornell University in collaboration with Joseph LeDoux’s laboratory at New York University is currently studying patients suffering from PTSD for any trauma. By having an individual take propranolol following a traumatic memory, they hope to interfere with the automatic association between the memory of the trauma and the hyperarousal symptoms and also to lessen the frequency of nightmares and flashbacks.
These exciting innovations may provide new possibilities for individuals suffering from the debilitating symptoms of PTSD. Some may be successful in helping individuals who have not responded to traditional treatments while others may engage patients who have heretofore refused to seek help. Indeed, they are indicative of a dynamic field that is expanding its horizons in the hope of offering relief to those who are in need.
JoAnn Difede, PhD is Associate Professor of Psychology in Psychiatry at Weill Cornell Medical College and Associate Attending Psychologist at NewYork Presbyterian Hospital (Manhattan). Judith Cukor, PhD is Assistant Professor of Psychology in Psychiatry at Weill Cornell Medical College and Assistant Attending Psychologist at NewYork-Presbyterian Hospital (Manhattan).
