"Cognitively demanding goal-directed tasks in the human brain are thought to involve the dynamic interplay of several large-scale neural networks, including the default-mode network (DMN), salience network (SN), and central-executive network (CEN). "
"Default mode network (DMN), central executive network (CEN) and salience network (SN) are the three most important intrinsic networks of the human brain. Recent studies emphasized the importance of the "triple-network model" which illustrated the interactions within and between DMN, CEN and SN in the pathophysiology of psychiatric disorders. However, previous studies of obsessive-compulsive disorder (OCD) just explored the altered connectivity within these networks while neglected the coupling between them. Hence, the present study was designed to fill this research gap.
Not only impaired coupling within the brain core intrinsic large-scale networks, but also coupling between large-scale neurocognitive networks, which reflect the difficulties in switching between task-negative and task-positive processing modes are involved in the neurobiological mechanism of OCD."
Cognitive vulnerability to Depression
"Figure 1: Aberrant intrinsic network interaction model that integrates the dual-process model of cognitive vulnerability, which has been adapted from Beevers (2005).14 The dual-process model includes two modes of information processing: (1) an associative mode involving quick, effortless processing, and (2) a reflective mode involving slow, effortful processing. We propose that abnormally increased resting-state DMN activity and connectivity, along with the corresponding biased associative processing (depressive rumination), contribute to the foundation of cognitive vulnerability. In the period of rest-to-task transition, aberrant network interactions contribute to three scenarios in which an associative bias cannot be corrected, thus promoting cognitive vulnerability. These three scenarios are (1) DMN dominance over the CEN (cognitive-resource depletion), (2) abnormal SN switching between the DMN and CEN (associative bias does not violate internal expectancies and trigger reflective processing), and (3) failure to activate the CEN effectively (reflective processing being triggered but failing to accurately adjust associative bias). As a result, a feedback loop between negative bias and dysphoria occurs, leading to a downward spiral. The solid lines in the triple-network model indicate enhanced interactions, while the dotted lines indicate attenuated interactions. CEN, central executive network; DMN, default mode network; SN, salience network."
"Specifically, aberrant resting-state activity and functional connectivity in cortical midline structures have been reliably observed in at-risk,22,23 depressed,24,25 and formerly depressed populations.26,27 Moreover, abnormality in the default-mode network (DMN), a principal intrinsic brain network including cortical midline structures, is increasingly associated with cognitive vulnerability among at-risk and depressed individuals.28,29 Other large-scale neural networks, such as the central executive network (CEN) and salience network (SN), also seem to play a role in biased attention and processing of affective information in depression.30–32 Thus, understanding how there might be simultaneous dysfunction in multiple networks (see Text Box 2) may elucidate the neural nature of cognitive vulnerability.37,48,49"
Borderline Personality
Inter-iFC (intrinsic functional connectivity) between two networks is based on Pearson’s correlation between network time courses
"Borderline personality disorder (BPD) is characterized by “stable instability” of emotions and behavior and their regulation. This emotional and behavioral instability corresponds with a neurocognitive triple network model of psychopathology, which suggests that aberrant emotional saliency and cognitive control is associated with aberrant interaction across three intrinsic connectivity networks [i.e., the salience network (SN), default mode network (DMN), and central executive network (CEN)]. The objective of the current study was to investigate whether and how such triple network intrinsic functional connectivity (iFC) is changed in patients with BPD. We acquired resting-state functional magnetic resonance imaging (rs-fMRI) data from 14 patients with BPD and 16 healthy controls. High-model order independent component analysis was used to extract spatiotemporal patterns of ongoing, coherent blood-oxygen-level-dependent signal fluctuations from rs-fMRI data. Main outcome measures were iFC within networks (intra-iFC) and between networks (i.e., network time course correlation inter-iFC). Aberrant intra-iFC was found in patients’ DMN, SN, and CEN, consistent with previous findings. While patients’ inter-iFC of the CEN was decreased, inter-iFC of the SN was increased. In particular, a balance index reflecting the relationship of CEN- and SN-inter-iFC across networks was strongly shifted from CEN to SN connectivity in patients. Results provide first preliminary evidence for aberrant triple network iFC in BPD. Our data suggest a shift of inter-network iFC from networks involved in cognitive control to those of emotion-related activity in BPD, potentially reflecting the persistent instability of emotion regulation in patients."
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Figure 1.
Default Mode Network. We defined 10 ROIs composing regions central to the default mode network (DMN). (A) A 3D video of our a priori regions of interest in free space. (B) Regions included the medial prefrontal cortex, posterior cingulate cortex, and bilateral complements of the dorsal superior frontal gyrus (dSFG), temporal pole, hippocampus, and angular gyrus.
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