title: Test-retest reproducibility of the default-mode network in healthy individuals.
abstract: Independent component analysis (ICA) of functional magnetic resonance imaging (fMRI) time-series reveals distinct coactivation patterns in the resting brain representing spatially coherent spontaneous fluctuations of the fMRI signal. Among these patterns, the so-called default-mode network (DMN) has been attributed to the ongoing mental activity of the brain during wakeful resting state. Studies suggest that many neuropsychiatric diseases disconnect brain areas belonging to the DMN. The potential use of the DMN as functional imaging marker for individuals at risk for these diseases, however, requires that the components of the DMN are reproducible over time in healthy individuals. In this study, we assessed the reproducibility of the DMN components within and between imaging sessions in 18 healthy young subjects (mean age, 27.5 years) who were scanned three times with two resting state scans during each session at 3.0 T field strength. Statistical analysis of fMRI time-series was done using ICA implemented with BrainVoyager QX. At all three sessions the essential components of the DMN could be identified in each individual. Spatial extent of DMN activity and size of overlap within and between sessions were most reproducible for the anterior and posterior cingulate gyrus. The degree of reproducibility of the DMN agrees with the degree of reproducibility found with motor paradigms. We conclude that DMN coactivation patterns are reproducible in healthy young subjects. Therefore, these data can serve as basis to further explore the effects of aging and neuropsychiatric diseases on the DMN of the brain.
authors.affiliation: Institute for Clinical Radiology, University of Munich, Ziemssenstrasse 1, Munich, Germany. Thomas.meindl@med.uni-muenchen.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Meindl
authors.forename: Stefan
authors.initials: S
authors.lastname: Teipel
authors.forename: Rachid
authors.initials: R
authors.lastname: Elmouden
authors.forename: Sophia
authors.initials: S
authors.lastname: Mueller
authors.forename: Walter
authors.initials: W
authors.lastname: Koch
authors.forename: Olaf
authors.initials: O
authors.lastname: Dietrich
authors.forename: Ute
authors.initials: U
authors.lastname: Coates
authors.forename: Maximilian
authors.initials: M
authors.lastname: Reiser
authors.forename: Christian
authors.initials: C
authors.lastname: Glaser
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D006179:Gyrus Cinguli / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D009483:Neuropsychological Tests; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D012984:Software; D055815:Young Adult