Resting-state theta band connectivity and graph analysis in generalized social anxiety disorder

Abstract

BackgroundFunctional magnetic resonance imaging (fMRI) resting-state studies show generalized social anxiety disorder (gSAD) is associated with disturbances in networks involved in emotion regulation, emotion processing, and perceptual functions, suggesting a network framework is integral to elucidating the pathophysiology of gSAD. However, fMRI does not measure the fast dynamic interconnections of functional networks. Therefore, we examined whole-brain functional connectomics with electroencephalogram (EEG) during resting-state.MethodsResting-state EEG data was recorded for 32 patients with gSAD and 32 demographically-matched healthy controls (HC). Sensor-level connectivity analysis was applied on EEG data by using Weighted Phase Lag Index (WPLI) and graph analysis based on WPLI was used to determine clustering coefficient and characteristic path length to estimate local integration and global segregation of networks.ResultsWPLI results showed increased oscillatory midline coherence in the theta frequency band indicating higher connectivity in the gSAD relative to HC group during rest. Additionally, WPLI values positively correlated with state anxiety levels within the gSAD group but not the HC group. Our graph theory based connectomics analysis demonstrated increased clustering coefficient and decreased characteristic path length in theta-based whole brain functional organization in subjects with gSAD compared to HC.ConclusionsTheta-dependent interconnectivity was associated with state anxiety in gSAD and an increase in information processing efficiency in gSAD (compared to controls). Results may represent enhanced baseline self-focused attention, which is consistent with cognitive models of gSAD and fMRI studies implicating emotion dysregulation and disturbances in task negative networks (e.g., default mode network) in gSAD.

Atypical functional connectivity in adolescents and adults with persistent and remitted ADHD

“…Unthresholded weighted iCoh matrices were used, in line with previous studies (6,(68)(69)(70), where each connection is equivalent to the measured iCoh of two electrodes. Graph-theory metrics measure the degree of network segregation (i.e., the tendency of brain regions to form local clusters with dense functional interconnections), and network integration and efficiency (i.e., the capacity of the network to become interconnected and efficiently exchange information between brain regions) (2,71).…”

“…Graph-theory metrics measure the degree of network segregation (i.e., the tendency of brain regions to form local clusters with dense functional interconnections), and network integration and efficiency (i.e., the capacity of the network to become interconnected and efficiently exchange information between brain regions) (2,71). The following commonly-used graph measures were calculated (6,49,69,72,73) correctly-and incorrectly-responded trials in stimulus-locked windows, before target (pre-stimulus; -500-0 ms) and during target processing (post-stimulus; 0-500 ms).…”

Valerian extract alters functional brain connectivity: A randomized double‐blind placebo‐controlled trial

“…Despite using different methods, other studies have reported that increased theta power and connectivity is related to dysfunctions in affective disorders such as depression, obsessive–compulsive disorder, and posttraumatic stress disorder (Imperatori et al, ; Kopřivová et al, ; Leuchter, Cook, Hunter, Cai, & Horvath, ). Whole‐brain resting‐state theta‐based connectivity is stronger in patients with social anxiety disorders than in healthy controls and is positively associated with state anxiety levels (Xing et al, ). Theta power and coherence increase when an individual engages in personal rumination (Andersen, Moore, Venables, & Corr, ), and increased theta coherence represents attention to negative thoughts or emotions (Xing et al, ).…”

“…Whole‐brain resting‐state theta‐based connectivity is stronger in patients with social anxiety disorders than in healthy controls and is positively associated with state anxiety levels (Xing et al, ). Theta power and coherence increase when an individual engages in personal rumination (Andersen, Moore, Venables, & Corr, ), and increased theta coherence represents attention to negative thoughts or emotions (Xing et al, ). Especially, significantly decreased theta coherences were observed over medial frontal electrodes centered on Fz (Figure b).…”

Human neurophysiological markers of high anxiety level during preparation for visual recognition

“…The processes underlying cortical resting-state electrical activity changes in anxious people are actually well understood [3][4][5][6][7][8][9], so are the neurophysiological mechanisms of facial expression recognition in such subjects [10][11][12]. It has been shown that both anxiety and depression, influence recognition of facial expression [13,14].…”