Parallel Interdigitated Distributed Networks within the Individual Estimated by Intrinsic Functional Connectivity

Rodrigo M Braga; Randy L Buckner

doi:10.1016/j.neuron.2017.06.038

Parallel Interdigitated Distributed Networks within the Individual Estimated by Intrinsic Functional Connectivity

Neuron. 2017 Jul 19;95(2):457-471.e5. doi: 10.1016/j.neuron.2017.06.038.

Authors

Rodrigo M Braga¹, Randy L Buckner²

Affiliations

¹ Department of Psychology, Center for Brain Science, Harvard University, Cambridge, MA 02138, USA; The Computational, Cognitive & Clinical Neuroimaging Laboratory, Hammersmith Hospital Campus, Imperial College London, London W12 0NN, UK; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA 02129, USA. Electronic address: rodrigo.braga@imperial.ac.uk.
² Department of Psychology, Center for Brain Science, Harvard University, Cambridge, MA 02138, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA 02129, USA; Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129, USA. Electronic address: randy_buckner@harvard.edu.

Abstract

Certain organizational features of brain networks present in the individual are lost when central tendencies are examined in the group. Here we investigated the detailed network organization of four individuals each scanned 24 times using MRI. We discovered that the distributed network known as the default network is comprised of two separate networks possessing adjacent regions in eight or more cortical zones. A distinction between the networks is that one is coupled to the hippocampal formation while the other is not. Further exploration revealed that these two networks were juxtaposed with additional networks that themselves fractionate group-defined networks. The collective networks display a repeating spatial progression in multiple cortical zones, suggesting that they are embedded within a broad macroscale gradient. Regions contributing to the newly defined networks are spatially variable across individuals and adjacent to distinct networks, raising issues for network estimation in group-averaged data and applied endeavors, including targeted neuromodulation.

Keywords: association cortex; brain systems; default network; dorsal attention network; frontoparietal network; hippocampus; memory.

MeSH terms

Brain Mapping*
Cerebral Cortex / physiology*
Hippocampus / physiology*
Humans
Image Processing, Computer-Assisted / methods
Magnetic Resonance Imaging / methods
Nerve Net / pathology*
Neural Pathways / physiology*

Abstract

MeSH terms

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