Summer has just arrived and with it the desire to switch off and break out of everyday life is becoming increasingly urgent. However, some questions arise: Is it really possible to quiet your brain? Can we give our brain free time without performing a specific task? Francis Eustache, neuropsychologist, President of the Scientific Council of the B2V Observatory of Memories, helps us to understand how our brain works at rest and decodes the phenomenon of network from default mode to rest.
“Turn off” the brain, is that possible?
Without a specific task, our brain still uses 20% of our body’s energy resources, which is only 5% less than when it has to do mental arithmetic or concentrate on a problem. The brain areas that then become active together form the “Default Mode Network”. They are mainly located on the midline, on the inner surface of the two cerebral hemispheres.
It is therefore not really possible to speak of rest for the brain. This is always active, even if it has no task to fulfill.
The network in standard mode
Described relatively recently, in the late 1990s and early 2000s, this phenomenon is a neurophysiological process highlighted by imaging of the brain, first with positron emission tomography (PET), then with resting-state functional magnetic resonance imaging (fMRI). .
The default mode is one of introspection, our inner thoughts. It is the place of synthesis, but also of creativity and adaptation. The brain projects itself, even in sometimes unlikely scenarios. This network is connected to that of our episodic memory, which houses our memories, our projects, and our understanding of others. It therefore plays an important role in our memory, in the construction of our identity and in our mental balance. It is also involved in many neurological disorders such as Alzheimer’s disease or certain mental disorders or even depression.
The default mode network plays a central role and is connected to many other brain areas that it can solicit depending on the nature and richness of the ongoing mental activity. But if our “daydreams” are suddenly interrupted, the brain can immediately switch to a controlled mode in which we react, for example, to an animal crossing a country road while driving.
Network functions in standard mode
- A guard role. The subject observes the surroundings diffusely.
- At the same time, the individual turns to himself, to his inner thoughts, to the past (autobiographical memory), to the future. He turns to an imaginative thought, more or less imaginative, not necessarily structured…
Hiking and running are also good examples of when Network Mode kicks in in Standard Mode.
” At this beginning of summer, let’s try to find some peace and time to find ourselves, but also to find others. Neuroscience has taught us the existence of this default mode cerebral network, whose task is very different from the other cognitive functions: language, perception, memory, reasoning… It is a privileged tool to detach us from an overly intrusive immediate present and dreaming aloud, imagining taking enough distance before the tumult of the start of the school year. » points to Francis Eustache, neuropsychologist, President of the Scientific Council of the B2V Observatory of Memories
About the B2V Observatory of Memories
Founded in April 2013 by the B2V Social Protection Group, the B2V Observatory of Memories studies memory in all its forms: individual, collective, digital… Its scientific advice brings together outstanding researchers from the neurosciences and human sciences. The actions carried out within the framework of this “social laboratory” aim to promote prevention through two main areas: supporting research and disseminating scientific advances to as many people as possible, by popularizing scientific information to facilitate their understanding .
To name just a few of the actions carried out by the Endowment Fund Observatoire B2V des Mémoires: the doctoral scholarship; the publication of books on memory; the public event La Semaine de la Mémoire; the edutainment site memorya.org; the memory accelerator at the service of social innovation.