Neuroscience : Idle minds : Nature News & Comment

Some circuits must remain active; they control automatic functions such as breathing and heart rate. But much of the rest of the brain continues to chug away as the mind naturally wanders through grocery lists, rehashes conversations and just generally daydreams. This activity has been dubbed the resting state. And neuroscientists have seen evidence that the networks it engages look a lot like those that are active during tasks.

Resting activity might be keeping the brain’s connections running when they are not in use. Or it could be helping to prime the brain to respond to future stimuli, or to maintain relationships between areas that often work together to perform tasks. It may even consolidate memories or information absorbed during normal activity.

“There’s so much enthusiasm about the approach now, and so little basic understanding,” says Michael Greicius, a neuroscientist at Stanford University in California, who started studying resting-state networks a decade ago.

Kleinschmidt suspects that the brain is running several models of the world in the background, ready for one of them to turn into reality. “Ideally, you’re always prepared for what happens next,” he says.

“the brain is not only thinking about supper coming up, but it’s also processing the recent past and converting some of that into long-term memories”, says Miall.

#cerveau
#Husserl pour la variation eidétique
#Nietzsche pour le brouillage #passivité/#activité

Et là, on voit soudain la #critique fondée physiologiquement :

“If you have random patterns of activity washing through your network, those can help reduce the strength of the pathways associated with what you’ve just learned.” That would stop the brain from reinforcing the same pathways too often. “Perhaps down-time periods are also important for that,” he says.

merci !

When a researcher slides someone into a scanner and instructs them to think about nothing in particular, there is no task to do and no hypothesis to address. So researchers have to generate reams of #data and line up hypotheses as they go along. “Resting state opens up discovery science,” says Milham enthusiastically, before admitting that, because he trained as a hypothesis-driven cognitive neuroscientist, “it’s like heresy that I’ve got into this”.

Whatever resting activity is doing, its existence certainly proves one thing. Miall puts it bluntly: “The brain only rests when you’re dead.”