Meta-Analysis of 89 Structural MRI Studies in Posttraumatic Stress Disorder and Comparison With Major Depressive Disorder

Abstract

Objective To conduct a comprehensive meta-analysis of MRI region-of-interest and voxel-based morphometry (VBM) studies in posttraumatic stress disorder (PTSD). As patients have high rates of comorbid depression an additional objective was to compare the findings to a meta-analysis of MRI studies in depression. Method The MEDLINE database was searched for studies from 1985 through 2016. A total of 113 studies met inclusion criteria and were included in an online database. Of these, 66 were selected for the region-of-interest meta-analysis and 13 for the VBM meta-analysis. The region-of-interest meta-analysis was conducted and compared with a meta-analysis of major depressive disorder. Within the region-of-interest meta-analysis, three subanalyses that included control groups with and without trauma were conducted. Results In the region-of-interest meta-analysis, patients with PTSD compared with all control subjects were found to have reduced brain volume, intracranial volume, and volumes of the hippocampus, insula, and anterior cingulate. PTSD patients compared with nontraumatized or traumatized control subjects showed similar changes. Traumatized compared with nontraumatized control subjects showed smaller volumes of the hippocampus bilaterally. For all regions, pooled effect sizes (Hedges’ g) varied from −0.84 to 0.43, and number of studies from three to 41. The VBM meta-analysis revealed prominent volumetric reductions in the medial prefrontal cortex, including the anterior cingulate. Compared with region-of-interest data from patients with major depressive disorder, those with PTSD had reduced total brain volume, and both disorders were associated with reduced hippocampal volume. Conclusions The meta-analyses revealed structural brain abnormalities associated with PTSD and trauma and suggest that global brain volume reductions distinguish PTSD from major depression.

Neural Bases of Cognitive Impairments in Post-Traumatic Stress Disorders: A Mini-Review of Functional Magnetic Resonance Imaging Findings

“…Furthermore, this result is also supported by behavioral data, suggesting that subjects affected by PTSD have poor performance in memory tasks, including both neutral and emotional stimuli, as well as severe difficulties in retrieving neutral words and autobiographical episodes (42). Finally, several neuroimaging studies also reported smaller hippocampal volumes in individuals with PTSD and abnormal hippocampal activity both during encoding and retrieval processes (4,43,44), ultimately suggesting that the hippocampus is a fundamental structure for cognitive and emotional processes in PTSD.…”

“…Interestingly, in recent years, neuroimaging investigations have provided important insight on the neurobiological underpinnings of these cognitive deficits in PTSD patients. Specifically, structural and resting-state MRI studies on PTSD reported gray matter and connectivity alterations in cortical areas, such as anterior cingulate cortex (ACC), prefrontal cortex (PFC) and insula, as well as in subcortical structures, such as hippocampus and amygdala (4), all regions known to be part of a network which regulates contextual processing (5). Finally, disproportional hypervigilance and tendency to interpret neutral or safe situations as dangerous have also been considered hallmarks of PTSD (5), further supporting the presence of a dysregulation in the contextual processing network in PTSD patients, which in turn may explain impairments in modulating fear inhibition, emotion and attention regulation, as well as autonomic responses (3,6,7).…”

Frontal Lobe Circuitry in Posttraumatic Stress Disorder

“… 57 , 61 , 104 – 109 Meta-analyses have confirmed findings of smaller dACC volume in people diagnosed with PTSD. 19 , 126 – 128 Reduced volume of the insular cortex has also been observed in PTSD. 57 , 60 , 62 , 105 , 108 , 110 Functionally, altered activation of the dACC and insular cortex in PTSD occurs during exposure to negative imagery.…”

Harassment, Bias, and the Evolving Politics of Free Speech on Campus

“…22 In these studies, subjects are first screened for the behavioral and psychological symptoms of PTSD and then independently their brains are (noninvasively) scanned. 22 In these studies, subjects are first screened for the behavioral and psychological symptoms of PTSD and then independently their brains are (noninvasively) scanned.…”

“…Magnetic resonance imaging (MRI) studies of humans with PTSD reveal that patients with PTSD "have reduced brain volume, intracranial volume, and volumes of the hippocampus, insula, and anterior cingulate." 22 In these studies, subjects are first screened for the behavioral and psychological symptoms of PTSD and then independently their brains are (noninvasively) scanned. The subject population includes controls who do not suffer from PTSD, and the scans are read without any knowledge of which subject group the scan was derived from.…”