Resting-state fMRI correlations: From link-wise unreliability to whole brain stability

• Published in: NeuroImage (Orlando, Fla.) Vol. 157; pp. 250 - 262
• Main Authors: Pannunzi, Mario, Hindriks, Rikkert, Bettinardi, Ruggero G., Wenger, Elisabeth, Lisofsky, Nina, Martensson, Johan, Butler, Oisin, Filevich, Elisa, Becker, Maxi, Lochstet, Martyna, Kühn, Simone, Deco, Gustavo
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 15.08.2017; Elsevier Limited; Elsevier
• Subjects: Adolescent; Adult; Basic Medicine; Biomarkers; Brain; Brain - diagnostic imaging; Brain architecture; Brain mapping; Connectome - standards; Female; Functional magnetic resonance imaging; Humans; Magnetic Resonance Imaging - standards; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Medicinska och farmaceutiska grundvetenskaper; Neural networks; Neurosciences; Neurovetenskaper; NMR; Nuclear magnetic resonance; Reproducibility of Results; Spatial heterogeneity; Studies; Young Adult
• ISSN: 1053-8119; 1095-9572; 1095-9572
• DOI: 10.1016/j.neuroimage.2017.06.006

The functional architecture of spontaneous BOLD fluctuations has been characterized in detail by numerous studies, demonstrating its potential relevance as a biomarker. However, the systematic investigation of its consistency is still in its infancy. Here, we analyze within- and between-subject variability and test-retest reliability of resting-state functional connectivity (FC) in a unique data set comprising multiple fMRI scans (42) from 5 subjects, and 50 single scans from 50 subjects. We adopt a statistical framework that enables us to identify different sources of variability in FC. We show that the low reliability of single links can be significantly improved by using multiple scans per subject. Moreover, in contrast to earlier studies, we show that spatial heterogeneity in FC reliability is not significant. Finally, we demonstrate that despite the low reliability of individual links, the information carried by the whole-brain FC matrix is robust and can be used as a functional fingerprint to identify individual subjects from the population.