Elucidating the function of brain resting‐state networks and their relation to the pathophysiology of neuropsychiatric diseases

• Published in: Neurology and clinical neuroscience 2021-01, Vol.9 (1), p.30-36
• Main Author: Yamashita, Ken‐ichiro
• Format: Article
• Language: English
• Subjects: Alzheimer's disease; Beta protein; Brain mapping; Cognitive ability; Deactivation; default mode network; Functional magnetic resonance imaging; Magnetic resonance imaging; Mental disorders; Neural networks; Neurodegenerative diseases; Neuroimaging; Physiology; Positron emission tomography; resting‐state fMRI; resting‐state networks
• ISSN: 2049-4173; 2049-4173
• DOI: 10.1111/ncn3.12403

At the end of the 1990s, PET studies revealed synchronized deactivation during cognitive tasks in a network of dissociated brain regions named the default mode network. In addition to default mode network deactivation during cognitive tasks, hyperactivation of the default mode network during non‐cognitive activities such as mind‐wandering state has been revealed by resting‐state functional magnetic resonance imaging studies. Progress in magnetic resonance imaging devices and analysis methods have allowed the physiological dynamics of functional brain networks to be elucidated as either task‐negative resting‐state networks such as the default mode network or task‐positive networks. Moreover, the anatomical overlap between brain areas with reduced mental load‐dependent default mode network deactivation and those with amyloid beta protein deposition in patients with Alzheimer's disease suggests a close interaction between abnormalities in functional connectivity and aggregation of the pathological protein. Apart from Alzheimer's disease, recent resting‐state functional magnetic resonance imaging studies have additionally revealed associations not only of dysfunctional resting‐state networks with neurodegenerative diseases, but also with various psychiatric disorders. Below we outline the physiological characteristics of brain resting‐state networks and their relation to the progression of neuropsychiatric diseases. The aim of this paper was to provide evidence that resting‐state networks are crucial for understanding the mechanisms of human cognitive function.