Impact of sampling rate on statistical significance for single subject fMRI connectivity analysisopen access
- Authors
- James, O[James, Oliver]; Park, H[Park, Hyunjin]; Kim, SG[Kim, Seong-Gi]
- Issue Date
- 1-Aug-2019
- Publisher
- WILEY
- Keywords
- autocorrelation; functional connectivity; resting-state fMRI; sample Pearson correlation coefficient; temporal filtering; variance correction
- Citation
- HUMAN BRAIN MAPPING, v.40, no.11, pp.3321 - 3337
- Indexed
- SCIE
SCOPUS
- Journal Title
- HUMAN BRAIN MAPPING
- Volume
- 40
- Number
- 11
- Start Page
- 3321
- End Page
- 3337
- URI
- https://scholarworks.bwise.kr/skku/handle/2021.sw.skku/9075
- DOI
- 10.1002/hbm.24600
- ISSN
- 1065-9471
- Abstract
- A typical time series in functional magnetic resonance imaging (fMRI) exhibits autocorrelation, that is, the samples of the time series are dependent. In addition, temporal filtering, one of the crucial steps in preprocessing of functional magnetic resonance images, induces its own autocorrelation. While performing connectivity analysis in fMRI, the impact of the autocorrelation is largely ignored. Recently, autocorrelation has been addressed by variance correction approaches, which are sensitive to the sampling rate. In this article, we aim to investigate the impact of the sampling rate on the variance correction approaches. Toward this end, we first derived a generalized expression for the variance of the sample Pearson correlation coefficient (SPCC) in terms of the sampling rate and the filter cutoff frequency, in addition to the autocorrelation and cross-covariance functions of the time series. Through simulations, we illustrated the importance of the variance correction for a fixed sampling rate. Using the real resting state fMRI data sets, we demonstrated that the data sets with higher sampling rates were more prone to false positives, in agreement with the existing empirical reports. We further demonstrated with single subject results that for the data sets with higher sampling rates, the variance correction strategy restored the integrity of true connectivity.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - Information and Communication Engineering > School of Electronic and Electrical Engineering > 1. Journal Articles
![qrcode](https://api.qrserver.com/v1/create-qr-code/?size=55x55&data=https://scholarworks.bwise.kr/skku/handle/2021.sw.skku/9075)
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.