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Inter-Network High-Order Functional Connectivity (IN-HOFC) and its Alteration in Patients with Mild Cognitive Impairment

  • Han Zhang
  • Panteleimon Giannakopoulos
  • Sven Haller
  • Dinggang ShenEmail author
  • Seong-Whan Lee
  • Shijun QiuEmail author
Original Article
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Abstract

Little is known about the high-order interactions among brain regions measured by the similarity of higher-order features (other than the raw blood-oxygen-level-dependent signals) which can characterize higher-level brain functional connectivity (FC). Previously, we proposed FC topographical profile-based high-order FC (HOFC) and found that this metric could provide supplementary information to traditional FC for early Alzheimer’s disease (AD) detection. However, whether such findings apply to network-level brain functional integration is unknown. In this paper, we propose an extended HOFC method, termed inter-network high-order FC (IN-HOFC), as a useful complement to the traditional inter-network FC methods, for characterizing more complex organizations among the large-scale brain networks. In the IN-HOFC, both network definition and inter-network FC are defined in a high-order manner. To test whether IN-HOFC is more sensitive to cognition decline due to brain diseases than traditional inter-network FC, 77 mild cognitive impairments (MCIs) and 89 controls are compared among the conventional methods and our IN-HOFC. The result shows that IN-HOFCs among three temporal lobe-related high-order networks are dampened in MCIs. The impairment of IN-HOFC is especially found between the anterior and posterior medial temporal lobe and could be a potential MCI biomarker at the network level. The competing network-level low-order FC methods, however, either revealing less or failing to detect any group difference. This work demonstrates the biological meaning and potential diagnostic value of the IN-HOFC in clinical neuroscience studies.

Keywords

Functional magnetic resonance imaging (fMRI) Mild cognitive impairment (MCI) Alzheimer’s disease (AD) Functional connectivity Brain network High-order 

Notes

Acknowledgments

This work is supported in part by NIH grants (EB006733, EB008374, EB009634, MH100217, AG041721, AG049371 and AG042599). We have no conflict of interest to declare.

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Authors and Affiliations

  1. 1.Department of Radiology and BRICUniversity of North Carolina at Chapel HillChapel HillUSA
  2. 2.Division of PsychiatryGeneva University HospitalsGenevaSwitzerland
  3. 3.Affidea CDRC - Centre Diagnostique Radiologique de CarougeCarougeSwitzerland
  4. 4.Department of Surgical Sciences, RadiologyUppsala UniversityUppsalaSweden
  5. 5.Department of NeuroradiologyUniversity Hospital FreiburgFreiburgGermany
  6. 6.Faculty of MedicineUniversity of GenevaGenevaSwitzerland
  7. 7.Department of Brain and Cognitive EngineeringKorea UniversitySeoulRepublic of Korea
  8. 8.Department of RadiologyThe First Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhouChina

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