title: A systematic investigation of the invariance of resting-state network patterns: is resting-state fMRI ready for pre-surgical planning?
abstract: OBJECTIVE
  Measurements of resting-state networks (RSNs) have been used to investigate a wide range of diseases, such as dementia or epilepsy. This raises the question whether this method could also serve as a pre-surgical planning tool. Generating reliable functional connectivity patterns is of crucial importance, particularly for pre-surgical planning, as these patterns may directly affect the outcome.
  
  
  METHODS
  This study investigated the reproducibility of four commonly used resting-state conditions: fixation of a black crosshair on a white screen; fixation of the center of a black screen; eyes-closed and fixation of the words "Entspann dich!" (Engl., "relax"). Ten healthy, right-handed male subjects (mean age, 25 years; SD 2) participated in the experiment. The spatial overlap for different RSNs across the four conditions was calculated.
  
  
  RESULTS
  The spatial overlap across all four conditions was calculated for each seed region on a single subject and at the group level. Activation maps at the single-subject and group levels were highly stable, especially for the reading network (RNW). The lowest consistency measures were found for the visual network (VIN). At the single-subject level spatial overlap values ranged from 0.31 (VIN) to 0.45 (RNW).
  
  
  CONCLUSIONS
  These findings suggest that RSN measurements are a reliable tool to assess language-related networks in clinical settings. Generally, resting-state conditions showed comparable activation patterns, therefore no specific conditions appears to be preferable.
authors.affiliation: Department of Radiology, Division of Neuro- and Musculoskeletal Radiology, Medical University of Vienna Vienna, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Kollndorfer
authors.forename: F Ph S
authors.initials: FP
authors.lastname: Fischmeister
authors.forename: G
authors.initials: G
authors.lastname: Kasprian
authors.forename: D
authors.initials: D
authors.lastname: Prayer
authors.forename: V
authors.initials: V
authors.lastname: Schöpf
keywords: default mode network; fMRI; functional connectivity; reproducibility; resting-state; resting-state network (RSN)