Default mode network （默认网络）

Default Mode Network

1. 组成

Functional hubs: Information regarding the self

• Posterior cingulate cortex (PCC) & precuneus: Combines bottom-up (not controlled) attention with information from memory and perception. The ventral (lower) part of PCC activates in all tasks which involve the DMN including those related to the self, related to others, remembering the past, thinking about future, and processing concepts plus spatial navigation. The dorsal (upper) part of PCC involves involuntary awareness and arousal. The precuneus is involved in visual, sensorimotor, and attentional information.
• Medial prefrontal cortex (mPFC): Decisions about self processing such as personal information, autobiographical memories, future goals and events, and decision making regarding those personally very close such as family. The ventral (lower) part is involved in positive emotional information and internally valued reward.
• Angular gyrus: Connects perception, attention, spatial cognition, and action and helps with parts of recall of episodic memories

2. 功能（作用）

The default mode network is most commonly defined with resting state data by putting a seed in the posterior cingulate cortex and examining which other brain areas most correlate with this area. The DMN can also be defined by the areas deactivated during external directed tasks compared to rest.

3. 关联

The DMN has been shown to be negatively correlated with other networks in the brain such as attention networks. Evidence has pointed to disruptions in the DMN of people with Alzheimer's and autism spectrum disorder.

The default mode network has shown to deactivate during external goal-oriented tasks such as visual attention or cognitive working memory tasks, thus leading some researchers to label the network as the task-negative network.