The precuneus/posterior cingulate cortex plays a pivotal role in the default mode network: Evidence from a partial
Peter Fransson1, Guillaume Marrelec
1MR Research Center, Department of Clinical Neuroscience, Stockholm Brain Institute, Karolinska Institute, Stockholm, Sweden. Peter.Fransson@ki.se
Neuroimage
|July 5, 2008
Summary
This study reveals strong functional connectivity within the default mode network, particularly involving the precuneus/posterior cingulate cortex. These findings enhance our understanding of brain networks during rest and working memory tasks.
Area of Science:
- Neuroscience
- Cognitive Neuroscience
- Brain Imaging
Background:
- Intrinsic brain activity, observed via functional magnetic resonance imaging (fMRI), shows coherent signal changes in long-range neuronal networks.
- The default mode network (DMN) is a key focus for linking intrinsic activity to cognition and neurological disease.
Purpose of the Study:
- To assess functional connectivity within the DMN during rest and a working memory task.
- To investigate effective connectivity using a data-driven approach.
Main Methods:
- Partial correlation analysis was employed to examine region-by-region functional connectivity.
- fMRI data were collected during resting state and a continuous working memory task.
Main Results:
- Strong interactions were observed between the precuneus/posterior cingulate region and the rest of the DMN.
- High interaction between medial temporal lobes was noted, contrasting with weak interactions with other DMN regions.
- Significant connectivity was found between the precuneus/posterior cingulate cortex and the left inferior parietal lobe, and within medial prefrontal cortex sections.
Conclusions:
- The precuneus/posterior cingulate cortex plays a crucial role in the default mode network's functional organization.
- Understanding DMN connectivity provides insights into cognitive processes and potential alterations in disease states.
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