Gray Matter Abnormalities in Social Anxiety Disorder: Primary, Replication, and Specificity Studies

Abstract

Background Despite increasing evidence that neuroanatomical abnormalities underlie pathological anxiety, social anxiety disorder (SAD), although among the most common of anxiety disorders, has received little attention. Using Magnetic Resonance Imaging, we (1) examined grey matter (GM) differences between generalized SAD and healthy control groups; (2) retested the findings in an independent clinical sample; and (3) tested for specificity by contrasting the SAD group to a separate group of panic disorder (PD) subjects. Methods The primary SAD group (N=16) was required to meet DSM-IV criteria for SAD, with onset by age 30; controls (N=20) had no lifetime history of anxiety. The replication sample included 17 generalized SAD and 17 control subjects. The PD comparison group (N=16) was required to have no lifetime SAD. Images were acquired on a 1.5Tesla GE Signa MRI scanner using a 3D T1-weighted spoiled gradient recalled pulse sequence. Morphological differences were determined using voxel based morphometry, in SPM8. Results After adjusting for age, gender, and total intracranial volume, SAD (as compared to control) subjects had greater GM in the left parahippocampal and middle occipital, and bilateral supramarginal and angular cortices, and left cerebellum; and lower GM in bilateral temporal poles and left lateral orbitofrontal cortex. Cerebellar, parahippocampal, and temporal pole differences were observed in both samples, survived whole brain corrections, and were not observed in the PD group, pointing to relative specificity to SAD. Conclusions These findings parallel the functional literature on SAD, and suggest structural abnormalities underlying the functional disturbances.

The investigation of hippocampus and amygdala volume changes with MRI in patients with social anxiety disorder

“…In another study, Talati et al 21 showed that patients with SAD had a more gray matter volume in the left parahippocampal, midoccipital, bilateral supramarginal, and angular cortices and in the left cerebellum; whereas, there was less gray matter volume in the bilateral Anatolian Journal of Psychiatry 2018; 19(2):150-156 temporal pallor and left lateral orbitofrontal cortex.…”

Reduced Anterior Temporal and Hippocampal Functional Connectivity During Face Processing Discriminates Individuals with Social Anxiety Disorder from Healthy Controls and Panic Disorder, and Increases Following Treatment

“…Furthermore, since structural parcellation introduces arbitrary boundaries between regions (Smith et al, 2011), future methodological improvements could include functional parcellation so that the signal from each node region is adequately captured (Ugurbil et al, 2013). Future studies might also utilize a variety of imaging paradigms that activate different regions, such as speech anticipation, eye gaze (Schneier et al, 2009), and other structural imaging modalities Talati et al, 2013), as the best discrimination may ultimately result from combining several paradigms and imaging modalities that tap into various neural facets of the disorder.…”

“…Functional scans of two subjects (one control and one SAD) were unusable due to scanner technical issues, while a third subject was excluded because she was diagnosed with both SAD and PD. Recruitment and clinical procedures have been detailed elsewhere (Talati et al, 2013) and are described in more detail in Supplementary Methods.…”

Individual variation in the neural processes of motor decisions in the stop signal task: the influence of novelty seeking and harm avoidance personality traits

“…Glucose metabolism in the anterior PHG predicts anxious temperament and is a heritable trait in non-human primates (Oler et al 2010). Other recent studies have reported a positive correlation between PHG gray matter volume and anxiety traits or disorders (Wei et al 2014; Talati et al 2013; Yang et al 2013), reduced functional connectivity between the anterior cingulate cortex and left PHG during threat disengagement in anxious youth (Price et al 2014), altered activity and connectivity of the PHG in anxiety disorders (Arnold Anteraper et al 2014; Lemche et al 2013; Schlumpf et al 2013), all of which speaks broadly to a link between PHG and anxiety trait. The current observation of greater PHG activation during risk-taking in harm avoidant individuals supports this association.…”