title: Test-retest reliability of fMRI activation generated by different saccade tasks.
abstract: OBJECTIVE
  To assess the reproducibility of brain-activation and eye-movement patterns in a saccade paradigm when comparing subjects, tasks, and magnetic resonance (MR) systems.
  
  
  METHODS
  Forty-five healthy adults at two different sites (n = 45) performed saccade tasks with varying levels of target predictability: predictable (PRED), position predictable (pPRED), time predictable (tPRED), and prosaccade (SAC). Eye-movement pattern was tested with a repeated-measures analysis of variance. Activation maps reproducibility were estimated with the cluster overlap Jaccard index and signal variance coefficient of determination for within-subjects test-retest data, and for between-subjects data from the same and different sites.
  
  
  RESULTS
  In all groups latencies increased with decreasing target predictability: PRED < pPRED < tPRED < SAC (P < 0,001). Activation overlap was good to fair (>0.40) in all tasks in the within-subjects test-retest comparisons and poor (<0.40) in the tPRED for different subjects. The overlap of the different tasks for within-groups data was higher (0.40-0.68) than for the between-groups data (0.30-0.50). Activation consistency was 60-85% in the same subjects, 50-79% in different subjects, and 50-80% in different sites. In SAC, the activation found in the same and in different subjects was more consistent than in other tasks (50-80%).
  
  
  CONCLUSIONS
  The predictive saccade tasks produced evidence for brain-activation and eye-movement reproducibility.
authors.affiliation: NIF/LIM44, Faculty of Medicine, University of Sao Paulo, Brazil; Faculty of Psychology, Universidade Cruzeiro do Sul, Sao Paulo, Brazil.
authors.forename: Katerina
authors.initials: K
authors.lastname: Lukasova
authors.forename: Jens
authors.initials: J
authors.lastname: Sommer
authors.forename: Mariana P
authors.initials: MP
authors.lastname: Nucci-da-Silva
authors.forename: Gilson
authors.initials: G
authors.lastname: Vieira
authors.forename: Marius
authors.initials: M
authors.lastname: Blanke
authors.forename: Frank
authors.initials: F
authors.lastname: Bremmer
authors.forename: João R
authors.initials: JR
authors.lastname: Sato
authors.forename: Tilo
authors.initials: T
authors.lastname: Kircher
authors.forename: Edson
authors.initials: E
authors.lastname: Amaro
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D012016:Reference Values; D015203:Reproducibility of Results; D012438:Saccades / Q000502:physiology*; D012680:Sensitivity and Specificity
keywords: eye movements; fMRI; multicenter study; reproducibility; saccades