title: Post-traumatic stress symptoms correlate with smaller subgenual cingulate, caudate, and insula volumes in unmedicated combat veterans.
abstract: Prior studies have examined differences in brain volume between patients with post-traumatic stress disorder (PTSD) and control subjects. Convergent findings include smaller hippocampus and medial prefrontal cortex volumes in PTSD. However, post-traumatic stress symptoms (PTSS) exist on a spectrum, and neural changes may occur beyond the diagnostic threshold of PTSD. We examined the relationship between PTSS and gray matter among combat-exposed U.S. military veterans. Structural brain magnetic resonance imaging (MRI) was obtained on 28 combat veterans from Operations Enduring and Iraqi Freedom. PTSS were assessed using the Clinician-Administered PTSD Scale (CAPS). Thirteen subjects met criteria for PTSD. Subjects were unmedicated, and free of major comorbid psychiatric disorders. Images were analyzed using voxel-based morphometry, and regressed against the total CAPS score and trauma load. Images were subsequently analyzed by diagnosis of PTSD vs. non-PTSD. CAPS scores were inversely correlated with volumes of the subgenual cingulate (sgACC), caudate, hypothalamus, insula, and left middle temporal gyrus (MTG). Group contrast revealed smaller sgACC, caudate, hypothalamus, left insula, left MTG, and right MFG in the PTSD group. PTSS are associated with abnormalities in limbic structures that may underlie the pathophysiology of PTSD. These abnormalities exist on a continuum with PTSS, beyond a diagnosis of PTSD.
authors.affiliation: Department of Psychiatry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA. herringarj@gmail.com
authors.forename: Ryan
authors.initials: R
authors.lastname: Herringa
authors.forename: Mary
authors.initials: M
authors.lastname: Phillips
authors.forename: Jorge
authors.initials: J
authors.lastname: Almeida
authors.forename: Salvatore
authors.initials: S
authors.lastname: Insana
authors.forename: Anne
authors.initials: A
authors.lastname: Germain
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002421:Caudate Nucleus / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology*; D003130:Combat Disorders / Q000175:diagnosis / Q000473:pathology* / Q000523:psychology*; D015897:Comorbidity; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006179:Gyrus Cinguli / Q000473:pathology*; D006801:Humans; D007031:Hypothalamus / Q000473:pathology; D007090:Image Interpretation, Computer-Assisted; D054542:Iraq War, 2003-2011; D008016:Life Change Events; D008279:Magnetic Resonance Imaging; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000473:pathology / Q000523:psychology; D009929:Organ Size / Q000502:physiology; D012016:Reference Values; D013223:Statistics as Topic; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis / Q000473:pathology* / Q000523:psychology*; D013702:Temporal Lobe / Q000473:pathology; D014728:Veterans / Q000523:psychology*