Default mode network

Default Mode Network

The Default Mode Network (DMN) is a large-scale brain network primarily composed of the medial prefrontal cortex, posterior cingulate cortex/precuneus and angular gyrus. It is best known for being active when an individual is not focused on the outside world and the brain is at wakeful rest, such as during daydreaming and mind-wandering. However, it is also active when the individual is thinking about others, thinking about themselves, remembering the past, and planning for the future.

File:Default mode network–Wikipedia.jpg

The Default Mode Network in the human brain.

Structure[edit | edit source]

The DMN involves several distinct brain regions, including:

Medial Prefrontal Cortex (mPFC): This region is involved in decision making, self-reference, and the attribution of mental states to oneself and others.
Posterior Cingulate Cortex (PCC): This region is involved in memory retrieval and the conscious state.
Precuneus: This region is involved in episodic memory, visuospatial processing, reflections upon self, and aspects of consciousness.
Angular Gyrus (AG): This region is involved in a number of processes related to language, number processing and spatial cognition, memory retrieval, attention, and theory of mind.

Function[edit | edit source]

The DMN is active during passive rest and mind-wandering, which often involves thinking about others, thinking about oneself, remembering the past, and planning for the future. These states are often associated with self-referential and introspective activity. The DMN is also active during decision making and social processing.

Clinical significance[edit | edit source]

Alterations in the DMN are observed in a number of neurological and psychiatric disorders, including Alzheimer's disease, autism, schizophrenia, depression, chronic pain, posttraumatic stress disorder, and others. These alterations are often associated with symptoms of these disorders, such as memory loss in Alzheimer's disease and social deficits in autism.