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Definition and characterization of an extended multiple-demand network
J A Camilleri1, V I Müller1, P Fox2
1Research Centre Jülich, Institute of Neuroscience and Medicine (INM-1,7), 52425 Jülich, Germany; Institute of Systems Neuroscience, Heinrich Heine University, Universitätstraße 1, 40225 Düsseldorf, Germany; Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University, Universitätstraße 1, 40225 Düsseldorf, Germany.
Neuroimage
|October 15, 2017
Summary
This study defines an extended multiple-demand network (eMDN) crucial for executive functions (EF). The eMDN comprises a core network and task-specific regions, essential for higher cognitive operations like working memory, attention, and inhibition.
Area of Science:
- Neuroscience
- Cognitive Neuroscience
- Neuroimaging
Background:
- Executive functions (EF) rely on brain regions with broad applicability across behaviors.
- A multiple-demand (MD) system, showing conjoint activation across tasks, has been proposed.
- The MD system may comprise sub-networks specialized for distinct cognitive roles.
Purpose of the Study:
- To define an extended multiple-demand network (eMDN) using functional connectivity.
- To identify potential sub-networks within the eMDN based on connectivity and function.
- To elucidate the neural basis of executive functions.
Main Methods:
- Task-dependent and task-independent functional connectivity analyses.
- Seeding analyses from brain regions convergently activated in working memory, attention, and inhibition tasks.
- Investigating connectional and functional similarities to define sub-networks.
Main Results:
- A robust definition of an extended multiple-demand network (eMDN) was established.
- Evidence for a core network within the eMDN crucial for general EF was found.
- Additional regions were identified as being recruited by the eMDN based on specific task demands.
Conclusions:
- The proposed eMDN, with its core and adaptable components, provides a framework for understanding executive functions.
- The integrity of the eMDN's core is vital for higher cognitive operations.
- The network dynamically recruits additional areas to meet specific cognitive demands.
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