Default network

In neuroscience, the default mode network (DMN), (also default network, or default state network), is a network of interacting brain regions known to have activity highly correlated with each other and distinct from other networks in the brain.

The default mode network is most commonly shown to be active when a person is not focused on the outside world and the brain is at wakeful rest, such as during daydreaming and mind-wandering. But it is also active when the individual is thinking about others, thinking about themselves, remembering the past, and planning for the future. The network activates "by default" when a person is not involved in a task. Though the DMN was originally noticed to be deactivated in certain goal-oriented tasks and is sometimes referred to as the task-negative network, it can be active in other goal-oriented tasks such as social working memory or autobiographical tasks. The DMN has been shown to be negatively correlated with other networks in the brain such as attention networks. Thinking about others also could include guessing their thoughts, emotions, and psychological motivations.

Evidence has pointed to disruptions in the DMN with people with Alzheimer’s and autism spectrum disorder.

The default mode network is known to be involved in many seemingly different functions:

It is the neurological basis for the self:

Thinking about others:

Remembering the past and thinking about the future:

The default mode network is active during passive rest and mind-wandering. Mind-wandering usually involves thinking about others, thinking about one’s self, remembering the past, and envisioning the future.Electrocorticography studies (which involve placing electrodes on the surface of epileptic patient’s brains) have shown the default mode network becomes activated within an order of a fraction of a second after participants finish a task.

Studies have shown that when people watch a movie, listen to a story, or read a story, their DMNs are highly correlated with each other. DMNs are not correlated if the stories are scrambled or are in a language the person does not understand, suggesting that the network is highly involved in the comprehension and the subsequent memory formation of that story. The DMN is shown to even be correlated if the same story is presented to different people in different languages, further suggesting the DMN is truly involved in the comprehension aspect of the story and not the auditory or language aspect.

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Wikipedia