Impact of dissociation on exposure therapy for PTSD outcomes and Adherence among U.S. Military service members.

Emotional engagement is necessary for successful exposure therapy for posttraumatic stress disorder (PTSD), but dissociation is considered a barrier to emotional engagement. Virtual reality exposure therapy (VRE) uses multi-sensory virtual environments to increase emotional engagement during exposure therapy, and average treatment outcomes are comparable to traditional exposure therapy. However, individual factors (e.g., depression) can predict differential responses to VRE. Studies have yet to investigate whether VRE would be more effective in treating patients with dissociation compared to traditional PE. This secondary analysis of a randomized clinical trial explores whether dissociation predicts treatment outcomes to exposure therapy among active-duty soldiers (N = 108) diagnosed with PTSD. We also examine whether individuals reporting dissociative symptoms demonstrated differential treatment responses to VRE and PE. Results indicated a significant two-way interaction between dissociation and time in treatment, such that dissociation blunted the negative relationship between time and PTSD symptoms. Dissociation was not associated with treatment session attendance or drop out. Results also revealed no significant effect of treatment group (PE or VRE) on the relationship between dissociation and PTSD symptoms. Findings contribute to a body of literature supporting the potential clinical and research utility of a dissociative subtype of PTSD.

Virtual Standardized Patients for Mental Health Education.

PURPOSE OF REVIEW: The training of psychiatrists and other mental health professionals requires education on a range of interpersonal, communication, and psychotherapy techniques. Classroom and workshop training must be augmented by experiential learning with feedback for skill implementation with fidelity. Virtual standardized patients (VSPs) are computerized conversational agents that can support experiential learning through standardized, consequence-free training environments at reduced costs. RECENT FINDINGS: Research on mental health VSPs is rife with feasibility and acceptability pilot studies across various training populations and settings. Users have generally reported positive reactions to training with VSPs, though frustrations with some VSP speech recognition or VSP response relevance has been reported. Several studies have demonstrated a promising transfer of clinical skills from VSP training to human standardized patients and randomized trials supporting improved skill relative to reading or academic study are encouraging. As technology improves and natural language processing and accurate computer response generation for broad ranging conversational topics emerges, the field would benefit from research on the characteristics of effective VSPs for a range of purposes and trainee populations. Well-designed randomized evaluations of VSPs relative to best practices in education are needed, particularly regarding the impact of VSPs on clinical practice among actual patients.

Psychophysiology during exposure to trauma memories: Comparative effects of virtual reality and imaginal exposure for posttraumatic stress disorder.

BACKGROUND: This investigation involved an in-depth examination of psychophysiological responses during exposure to the trauma memory across 10 sessions among active duty soldiers with combat-related posttraumatic stress disorder (PTSD) treated by Prolonged Exposure (PE) or Virtual Reality Exposure (VRE). We compared psychophysiological changes, session-by-session, between VRE and traditional imaginal exposure. METHODS: Heart rate (HR), galvanic skin response (GSR), and peripheral skin temperature were collected every 5 min during exposure sessions with 61 combat veterans of Iraq/Afghanistan and compared to the PTSD Checklist (PCL-C) and Clinician-Administered PTSD Scale (CAPS) outcomes using multilevel modeling. RESULTS: Over the course of treatment, participants in the PE group had higher HR arousal compared to participants in the VRE group. With reference to GSR, in earlier sessions, participants demonstrated a within-session increase, whereas, in later sessions, participants showed a within-session habituation response. A significant interaction was found for GSR and treatment assignment for within-session change, within-person effect, predicting CAPS (d = 0.70) and PCL-C (d = 0.66) outcomes. CONCLUSION: Overall, these findings suggest that exposure to traumatic memories activates arousal across sessions, with GSR being most associated with reductions in PTSD symptoms for participants in the PE group.

Does Traumatic Brain Injury Attenuate the Exposure Therapy Process?

Research indicates that exposure therapy is efficacious for combat-related posttraumatic stress disorder (PTSD) comorbid with traumatic brain injury (TBI) as is shown by reduced PTSD treatment outcome scores. What is unknown, however, is whether the process of fear extinction is attenuated in veterans with TBI history. Increased PTSD symptomatology and possible cognitive deficits associated with TBI sequelae may indicate additional or longer exposure sessions to achieve habituation and extinction comparable to individuals without TBI history. As such, a more extensive course of treatment may be necessary to achieve comparable PTSD treatment outcome scores for individuals with TBI history. Using a sample of veterans with combat-related PTSD, some of whom were comorbid for TBI, this study compared process variables considered relevant to successful treatment outcome in exposure therapy. Individuals with and without TBI demonstrated similar rates of fear activation, length and number of exposure sessions, within-session habituation, between-session habituation, and extinction rate; results remained consistent when controlling for differential PTSD symptomatology. Furthermore, results indicated that self-perception of executive dysfunction did not impact the exposure process. Results suggest that individuals with PTSD and TBI history engage successfully and no differently in the exposure therapy process as compared to individuals with PTSD alone. Findings further support exposure therapy as a first-line treatment for combat-related PTSD regardless of TBI history.

Neurophysiological Response to Olfactory Stimuli in Combat Veterans With Posttraumatic Stress Disorder.

There is a need for a better understanding of underlying pathology in posttraumatic stress disorder (PTSD) to develop more effective treatments. The late positive potential (LPP) amplitude from electroencephalogram has been used to assess individual differences in emotional reactivity. There is evidence that olfaction is particularly important in emotional processing in PTSD. The current study examined LPP amplitudes in response to olfactory stimuli in 24 combat veterans with PTSD and 24 nonmilitary/non-PTSD controls. An olfactometer delivered three negatively valenced odorants, with 12 trials of each delivered in a random order. The groups did not differ in LPP amplitude across odorants. However, within the PTSD group, higher Clinician-Administered PTSD Scale scores related to an increased LPP amplitude after diesel fuel and rotten egg, but not n_butanol, odorants. Results provide specific targets and theory for further research into clinical applications such as selection of idiographic odorants for use in virtual-reality exposure therapy.

A Functional Near-Infrared Spectroscopy Study of Trauma-Related Auditory and Olfactory Cues: Posttraumatic Stress Disorder or Combat Experience?

The prevalence of posttraumatic stress disorder (PTSD) among U.S. veterans deployed to Iraq or Afghanistan necessitates the need for comprehensive assessment and treatment strategies. This study investigated the utility of a combat-related PTSD symptom provocation paradigm to elicit unique neurological responses across three groups: combat veterans with PTSD, combat veterans without PTSD, and nonmilitary participants without PTSD. Using functional near-infrared spectroscopy (fNIRS) the results indicated that combat veterans with PTSD demonstrated significant activation to a trauma-related sound compared with nonmilitary personnel, channel 14: d = 1.03, 95% confidence interval (CI) [0.28, 1.76]; channel 15: d = 1.30, 95% CI [0.53, 2.06]; and combat veterans without PTSD, channel 14: d = 0.87, 95% CI [0.14, 1.59]. Specifically, this increased neural activation was approximately located in the right medial superior prefrontal cortex (Brodmann areas 9/10), an area associated with experiencing negative or threatening stimuli and emotional detachment. There were no differences across the groups for nontrauma-related sounds. Results were less clear with respect to a combat-related odor. These results suggest a specific neurophysiological response to trauma-related cues and, if replicated, may offer a biomarker for combat-related PTSD. Such a response could provide incremental validity over diagnostic assessments alone and assist in planning and monitoring of treatment outcome.