Neurosubstrates of remission following prolonged exposure therapy in veterans with posttraumatic stress disorder.
BACKGROUND
Prolonged exposure (PE) therapy is the first-line treatment for posttraumatic stress disorder (PTSD) in combat veterans. The underlying brain changes of treatment effect in PTSD are currently unknown.


METHODS
A total of 31 veterans with PTSD completed an fMRI scan performing an affective anticipation task at baseline and were enrolled in PE therapy. Of these, 7 prematurely terminated therapy, while 24 individuals completed PE therapy and an identical follow-up fMRI scan. At follow-up, 15 of the 24 completers still had diagnosable PTSD (NR-PTSD) and 9 of the 24 completers showed complete remission from PTSD (R-PTSD), i.e. they did not meet diagnostic criteria for PTSD.


RESULTS
The left anterior insula showed a significant group by scan session interaction. Specifically, the R-PTSD group showed decreased activation during anticipation of negative images from pre- to posttreatment scans, while the NR-PTSD group showed increased activation during anticipation of positive images in this region. Furthermore, the change in functional activation in the insula co-occurred with increased connectivity between this insular region and the right cingulate and right mid-posterior insular region in R-PTSD.


CONCLUSIONS
These findings suggest that the capacity to effectively remit from PTSD symptoms after PE treatment requires the ability to connect with physiological signals and moderate the discomfort of anticipatory anxiety of exposure therapy. These processes appear to be controlled by a network where the anterior insula is connected with the cingulate and the mid-posterior insula.
VA San Diego Healthcare System, University of California San Diego, La Jolla, Calif., USA.
Alan N
AN
Simmons
Sonya B
SB
Norman
Andrea D
AD
Spadoni
Irina A
IA
Strigo
D000328:Adult; D059031:Anticipation, Psychological / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D006801:Humans; D007171:Implosive Therapy; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology* / Q000523:psychology / Q000628:therapy; D013997:Time Factors; D016896:Treatment Outcome; D014728:Veterans / Q000523:psychology*