title: A variance components model for statistical inference on functional connectivity networks.
abstract: We propose a variance components linear modeling framework to conduct statistical inference on functional connectivity networks that directly accounts for the temporal autocorrelation inherent in functional magnetic resonance imaging (fMRI) time series data and for the heterogeneity across subjects in the study. The novel method estimates the autocorrelation structure in a nonparametric and subject-specific manner, and estimates the variance due to the heterogeneity using iterative least squares. We apply the new model to a resting-state fMRI study to compare the functional connectivity networks in both typical and reading impaired young adults in order to characterize the resting state networks that are related to reading processes. We also compare the performance of our model to other methods of statistical inference on functional connectivity networks that do not account for the temporal autocorrelation or heterogeneity across the subjects using simulated data, and show that by accounting for these sources of variation and covariation results in more powerful tests for statistical inference.
authors.affiliation: Division of Biostatistics, University of Minnesota, Minneapolis, MN 55455, USA. Electronic address: mfiecas@umn.edu.
authors.forename: Mark
authors.initials: M
authors.lastname: Fiecas
authors.affiliation: Department of Finance and Statistical Analysis, Alberta School of Business, University of Alberta, Edmonton, AB, Canada T6G 2R6.
authors.forename: Ivor
authors.initials: I
authors.lastname: Cribben
authors.affiliation: Department of Communication Sciences and Disorders, Faculty of Rehabilitation Medicine and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada T6G 2G4.
authors.forename: Reyhaneh
authors.initials: R
authors.lastname: Bahktiari
authors.affiliation: Department of Communication Sciences and Disorders, Faculty of Rehabilitation Medicine and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada T6G 2G4.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Cummine
mesh_terms: D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008959:Models, Neurological; D009434:Neural Pathways / Q000502:physiology*; D055815:Young Adult
keywords: Dyslexia; Functional connectivity networks; Resting-state fMRI; Subject heterogeneity; Temporal autocorrelation