title: Integration of resting-state FMRI and diffusion-weighted MRI connectivity analyses of the human brain: limitations and improvement.
abstract: BACKGROUND
  Integration of functional connectivity analysis based on resting-state functional Magnetic Resonance Imaging (fMRI) and structural connectivity analysis based on Diffusion-Weighted Imaging (DWI) has shown great potential to improve understanding of the neural networks in the human brain. However, there are sensitivity and specificity-related interpretation issues that must be addressed.
  
  
  METHODS
  We assessed the long-range functional and structural connections of the default-mode, attention, visual and motor networks on 25 healthy subjects. For each network, we first integrated these two analyses based on one common seed region. We then introduced a functional-assisted fiber tracking strategy, where seed regions were defined based on independent component analysis of the resting-state fMRI dataset.
  
  
  RESULTS
  The single-seed based technique successfully identified the expected functional connections within these networks at both subject and group levels. However, the success rate of structural connectivity analysis showed a high level of variation among the subjects. The functional-assisted fiber tracking strategy highly improved the rate of successful fiber tracking.
  
  
  CONCLUSIONS
  This fMRI/DWI integration study suggests that functional connectivity analysis might be a more sensitive and robust approach in understanding the connectivity between cortical regions, and can be used to improve DWI-based structural connectivity analysis.
authors.affiliation: Departments of Psychology and Radiology, and Cognitive Imaging Research Center, Michigan State University.
authors.forename: David C
authors.initials: DC
authors.lastname: Zhu
authors.forename: Shantanu
authors.initials: S
authors.lastname: Majumdar
mesh_terms: D000328:Adult; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology*; D063132:Connectome / Q000379:methods*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008954:Models, Biological; D015233:Models, Statistical; D064847:Multimodal Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012146:Rest / Q000502:physiology*; D012680:Sensitivity and Specificity; D018511:Systems Integration
keywords: DWI tractography; Resting-state fMRI