Novel Treatment of Emotional Dysfunction in PTSD
We will first screen participants between the ages of 18 and 50 years with PTSD for the symptom of hyperarousal, as determined by subjective reporting of hyperarousal symptoms of PTSD. If these are present, a more extensive screening to determine the eligibility of each subject will be performed. This will be followed by an EEG. The EEG system measures event-related potentials (ERPs), which explain certain cognitive processes based on changes in the amplitude and timing of electrical changes recorded from the surface of the scalp. We will use an ERP task that includes combat-threatening stimuli as the novel oddball probe to assess P300 response. The amplitude of the P300 (positive amplitude recorded 300 milliseconds after stimulus onset) is used to differentiate between hypo-, normo-, and hyper-arousability. Identifying those with hyperarousal on P300 response on ERP allows for identification of PTSD patients with subjective and objective measures of hyperarousal. The participants will then be scheduled for a neuroimaging session. During neuroimaging, participants will have structural and functional brain scans acquired, including a functional MRI scan using the same threatening/nonthreatening stimuli, thus providing another objective measure of hyperarousal.
Participants will then have active or sham 1 Hz repetitive transcranial magnetic stimulation (rTMS) administered to the right frontal lobe as well as Cognitive Processing Therapy (CPT) once a week for twelve weeks (total 12 rTMS-CPT sessions). Studies have shown that rTMS applied externally to the forehead in the region of the dorsal lateral forehead will safely, reversibly, and painlessly down-modulate the frontal lobe on the side of the head to which it is applied. Our preliminary studies have shown that application of frontal rTMS can reduce the response to threatening stimuli temporarily and this can optimize the effectiveness of the CPT. Following the 12 sessions of rTMS-CPT, the EEG and neuroimaging will be repeated to test for changes in brain function.
The research objective will be to determine if adding rTMS prior to CPT significantly alters measures of arousal and improves clinical outcome.
Interpretative measures of treatment outcome:
a) Primary Study Endpoint: The CAPS-2 score changes for cluster [Left Quote]D[Right Quote]
b) Secondary Study Endpoints
i) Change in ERP measures of P3a amplitude for hyperarousal to combat threatening stimuli
ii) Change in the total CAPS-2 score
iii) Change in fMRI BOLD signals in the visual association cortices and amygdalae for hyperarousal to threatening stimuli.
c) Primary Study Safety Endpoints
i) monitoring for worsening psychiatric symptoms
ii) monitoring for side effects from the TMS treatment
* male and female veterans of Operation Iraqi Freedom or Operation Enduring Freedom (OIF/OEF)
* between the ages of 18 and 50 years
* who have a diagnosis of PTSD
* English speakers