The default-mode network (DMN) is one of the human brain’s networks activated in resting and self-referential thinking states. The nature of this network and its normal or abnormal changes has been the subject of various studies. The aim of this study was to systematical review and integrating the findings of that studies focused on the relationship of DMN with mental disorders and aging-induced changes in it. Of the more than 100 evidences found, 32 studies in each of two specific subjects (psychopathologicaland aging-related changes of DMN) were selected and scientifically mentioned the most important results of them. Based on the findings, some of the mental disorders including major depression, generalized anxiety disorder, obsessive compulsive disorder, schizophrenia, attention-deficit hyperactivity disorder, and Alzheimer disease are associated with functional or connectional abnormalities in DMN. Aging can cause functional changes in the activation or deactivation of the DMN’s regions or inter/intra-network connectivity of this network. Although most of studies have a pathological perspective on DMN changes; one article pointed out the positive role of DMN changes during aging in terms of emotion regulation.
