title: Assessing the mean strength and variations of the time-to-time fluctuations of resting-state brain activity.
abstract: The time-to-time fluctuations (TTFs) of resting-state brain activity as captured by resting-state fMRI (rsfMRI) have been repeatedly shown to be informative of functional brain structures and disease-related alterations. TTFs can be characterized by the mean and the range of successive difference. The former can be measured with the mean squared successive difference (MSSD), which is mathematically similar to standard deviation; the latter can be calculated by the variability of the successive difference (VSD). The purpose of this study was to evaluate both the resting state-MSSD and VSD of rsfMRI regarding their test-retest stability, sensitivity to brain state change, as well as their biological meanings. We hypothesized that MSSD and VSD are reliable in resting brain; both measures are sensitive to brain state changes such as eyes-open compared to eyes-closed condition; both are predictive of age. These hypotheses were tested with three rsfMRI datasets and proven true, suggesting both MSSD and VSD as reliable and useful tools for resting-state studies.
authors.affiliation: Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, 3900 Chestnut St, Philadelphia, PA, 19104, USA.
authors.forename: Zhengjun
authors.initials: Z
authors.lastname: Li
authors.affiliation: Center for Cognition and Brain Disorders, Institutes of Neurological Science, Hangzhou Normal University, Hangzhou, 310005, Zhejiang Province, China.|Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, 310005, Zhejiang Province, China.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Zang
authors.affiliation: Affiliated Hospital, Hangzhou Normal University, 126 Wenzhou Rd, Building 7, MRI Room, Hangzhou, 310015, Zhejiang Province, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Ding
authors.affiliation: Center for Cognition and Brain Disorders, Institutes of Neurological Science, Hangzhou Normal University, Hangzhou, 310005, Zhejiang Province, China. redhatw@gmail.com.|Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, 310005, Zhejiang Province, China. redhatw@gmail.com.|Affiliated Hospital, Hangzhou Normal University, 126 Wenzhou Rd, Building 7, MRI Room, Hangzhou, 310015, Zhejiang Province, China. redhatw@gmail.com.
authors.forename: Ze
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001921:Brain / Q000000981:diagnostic imaging* / 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; D015203:Reproducibility of Results; D012146:Rest / Q000502:physiology*; D012737:Sex Factors
keywords: Fluctuation; Resting-state fMRI; Variation