Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Nov;69(11):1169-78.
doi: 10.1001/archgenpsychiatry.2012.50.

Amygdala volume changes in posttraumatic stress disorder in a large case-controlled veterans group

Rajendra A Morey  1 , Andrea L Gold, Kevin S LaBar, Shannon K Beall, Vanessa M Brown, Courtney C Haswell, Jessica D Nasser, H Ryan Wagner, Gregory McCarthy; Mid-Atlantic MIRECC Workgroup
Collaborators, Affiliations

Amygdala volume changes in posttraumatic stress disorder in a large case-controlled veterans group

Rajendra A Morey et al. Arch Gen Psychiatry. 2012 Nov.

Abstract

Context: Smaller hippocampal volumes are well established in posttraumatic stress disorder (PTSD), but the relatively few studies of amygdala volume in PTSD have produced equivocal results.

Objective: To assess a large cohort of recent military veterans with PTSD and trauma-exposed control subjects, with sufficient power to perform a definitive assessment of the effect of PTSD on volumetric changes in the amygdala and hippocampus and of the contribution of illness duration, trauma load, and depressive symptoms.

Design: Case-controlled design with structural magnetic resonance imaging and clinical diagnostic assessments. We controlled statistically for the important potential confounds of alcohol use, depression, and medication use.

Setting: Durham Veterans Affairs Medical Center, which is located in proximity to major military bases.

Patients: Ambulatory patients (n = 200) recruited from a registry of military service members and veterans serving after September 11, 2001, including a group with current PTSD (n = 99) and a trauma-exposed comparison group without PTSD (n = 101).

Main outcome measure: Amygdala and hippocampal volumes computed from automated segmentation of high-resolution structural 3-T magnetic resonance imaging.

Results: Smaller volume was demonstrated in the PTSD group compared with the non-PTSD group for the left amygdala (P = .002), right amygdala (P = .01), and left hippocampus (P = .02) but not for the right hippocampus (P = .25). Amygdala volumes were not associated with PTSD chronicity, trauma load, or severity of depressive symptoms.

Conclusions: These results provide clear evidence of an association between a smaller amygdala volume and PTSD. The lack of correlation between trauma load or illness chronicity and amygdala volume suggests that a smaller amygdala represents a vulnerability to developing PTSD or the lack of a dose-response relationship with amygdala volume. Our results may trigger a renewed impetus for investigating structural differences in the amygdala, its genetic determinants, its environmental modulators, and the possibility that it reflects an intrinsic vulnerability to PTSD.

PubMed Disclaimer

Conflict of interest statement

The authors have no conflicts of interest and no financial disclosures. The entities that provided funding support had no input into the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript. The principal investigator (Rajendra Morey, M.D.) had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Figures

Figure 1
Figure 1
Example of automated segmentation of the amygdala and hippocampus using FreeSurfer. The high-resolution structural MRI of a representative subject is displayed in radiological convention with segmentation labels for the amygdala (in blue) and hippocampus (in yellow) as shown in (A) sagittal (left hemisphere), (B) coronal, and (C) axial slices.
See this image and copyright information in PMC

References

    1. Rauch SL, Shin LM, Phelps EA. Neurocircuitry models of posttraumatic stress disorder and extinction: human neuroimaging research--past, present, and future. Biological Psychiatry. 2006 Aug 15;60(4):376–382. - PubMed
    1. Dunsmoor JE, Prince SE, Murty VP, Kragel PA, LaBar KS. Neurobehavioral mechanisms of human fear generalization. Neuroimage. 2011 Apr 15;55(4):1878–1888. - PMC - PubMed
    1. LaBar KS, Gatenby JC, Gore JC, LeDoux JE, Phelps EA. Human amygdala activation during conditioned fear acquisition and extinction: a mixed-trial fMRI study. Neuron. 1998;20(5):937–945. - PubMed
    1. Pape HC, Pare D. Plastic synaptic networks of the amygdala for the acquisition, expression, and extinction of conditioned fear. Physiol Rev. 2010 Apr;90(2):419–463. - PMC - PubMed
    1. McEwen BS. Physiology and neurobiology of stress and adaptation: Central role of the brain. Physiol Rev. 2007 Jul;87(3):873–904. - PubMed

Publication types

MeSH terms