Brain activity in the resting state: default mode network as an inside story within the brain

Abstract

As a promising research field after the turn of the new century, a default mode network (DMN) in the brain shows strong potential as a new breakthrough in neuroscience. This approach emphasizes the baseline of the brain's activities when the brain is awake but is not receiving any external input signal. The study of DMN has recently been highlighted, and is expected to provide a key to understanding mental disorders. This article consists of two sections: (1) a brief tutorial on DMN is presented, together with some necessary fundamental knowledge of neuroscience, and (2) a framework of network informatics for the DMN is proposed based on network dynamics. Models of information networks are discussed to bridge the gap between the level of regions and the level of neurons in the brain, and major issues about analyzing the DMN by brain imaging technologies are also discussed. One of the inspirations arising from the DMN approach is how spontaneous collective behavior emerges within an autonomous system. This is crucial to a systematic understanding of the brain's function, and to exploring some new design principles of autonomous robotics in order to demonstrate complex life-like behaviors in engineering.