Reduced resting-state functional connectivity between amygdala and orbitofrontal cortex in social anxiety disorder

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

“…Although previous studies have demonstrated differences in activation and FC Liao et al, 2010;Prater et al, 2012;Hahn et al, 2011;Klumpp et al, 2012) between SAD and HCs, the current work is the first to use FC (and activation) to discriminate SAD vs HC diagnostic membership. The current approach of combining machine learning with large-scale, condition-dependent FC is more exploratory and data driven in identifying FC differences than previously used techniques such as PPI Analysis, which only assess FC with a single, a priori specified, 'seed' region at a time.…”

Affect labeling enhances exposure effectiveness for public speaking anxiety

“…Perhaps more frequent use of affect labels during exposure led to greater activation in PFC-amygdala pathways. Participants with social anxiety show weaker connectivity between areas of the PFC and the amygdala (Hahn et al, 2011), and the number of repetitions of activation in PFC-amygdala pathways during exposure may positively correlate with the strength of PFC-amygdala connectivity following completion of exposure. Consistent with the principle of neural plasticity, which states that repetition of a process can increase efficiency and efficacy of that process through changes in neuron function, chemical profile, and structure (Anderson, 2010;Kandel & Schwartz, 1982), greater activation of PFC-amygdala neural pathways as a result of more frequent labeling may have produced greater neural change and ultimately more effective down regulation of physiological fear responding.…”

“…Patients with anxiety show deficits in prefrontal amygdala connectivity (Hahn et al, 2011;Kim et al, 2011), and repeated activation of prefrontal regions that project to the amygdala through exposure and affect labeling can lead to a reduction in physiological activation in response to an anxiety provoking stimulus. The results of the current study indicate that instruction to label emotional experiences improves physiological attenuation of fear, and that the more a fearful individual labels his or her emotional experience during exposure, the greater the reduction in galvanic skin response (a measure of fear arousal) when they next encounter the feared stimulus.…”

“…Assuming that extinction is a central mechanism of exposure therapy Craske, Liao, Brown, & Vervliet, 2012), PFC downregulation of amygdala may contribute to successful exposure therapy, and strategies that augment such downregulatory pathways may augment outcomes from exposure therapy. In addition, evidence suggests that patients with social anxiety disorder have weaker connectivity between the medial orbitofrontal PFC and the amygdala compared to healthy controls (Hahn et al, 2011). Therefore, treatments that strengthen connectivity between prefrontal regions and the amygdala may prove particularly beneficial in the treatment of social anxiety.…”

Hyper-Connectivity of Subcortical Resting-State Networks in Social Anxiety Disorder

“…Of the existing fcMRI studies involving SAD populations, a few studies studies Liao et al, 2010a;Liao et al, 2010b;Liao et al, 2011;Qiu et al, 2011) used identical acquisition parameters including low-resolution (3.75 x 3.75 x 5 mm) voxels. Of the remaining studies, one had very limited coil sensitivity to detect Blood Oxygenation Level Dependent (BOLD) signal from subcortical regions (Pannekoek et al, 2012), and two had limited head coverage and/or low resolution (Hahn et al, 2011;Prater et al, 2013). Since physiological noise, a major confound in fcMRI, dominates at low-resolution (Triantafyllou et al, 2005), highresolution imaging is desirable in this context.…”