Version 1
: Received: 28 February 2023 / Approved: 28 February 2023 / Online: 28 February 2023 (09:32:04 CET)
How to cite:
Rangaprakash, D.; Barry, R.; Deshpande, G. The Confound of Hemodynamic Response Function Variability in Resting-State Functional MRI Studies. Preprints2023, 2023020516. https://doi.org/10.20944/preprints202302.0516.v1
Rangaprakash, D.; Barry, R.; Deshpande, G. The Confound of Hemodynamic Response Function Variability in Resting-State Functional MRI Studies. Preprints 2023, 2023020516. https://doi.org/10.20944/preprints202302.0516.v1
Rangaprakash, D.; Barry, R.; Deshpande, G. The Confound of Hemodynamic Response Function Variability in Resting-State Functional MRI Studies. Preprints2023, 2023020516. https://doi.org/10.20944/preprints202302.0516.v1
APA Style
Rangaprakash, D., Barry, R., & Deshpande, G. (2023). The Confound of Hemodynamic Response Function Variability in Resting-State Functional MRI Studies. Preprints. https://doi.org/10.20944/preprints202302.0516.v1
Chicago/Turabian Style
Rangaprakash, D., Robert Barry and Gopikrishna Deshpande. 2023 "The Confound of Hemodynamic Response Function Variability in Resting-State Functional MRI Studies" Preprints. https://doi.org/10.20944/preprints202302.0516.v1
Abstract
Functional magnetic resonance imaging (fMRI) is an indirect measure of neural activity with the hemodynamic response function (HRF) coupling it with unmeasured neural activity. The HRF, modulated by several non-neural factors, is variable across brain regions, individuals and populations. Yet, a majority of resting-state fMRI connectivity studies continue to assume a non-variable HRF. In this article, with supportive prior evidence, we argue that HRF variability cannot be ignored as it substantially confounds within-subject connectivity estimates and between-subjects connectivity group differences. We also discuss its clinical relevance with connectivity impairments confounded by HRF aberrations in several disorders. We present limited data on HRF differences between women and men, which resulted in a 15.4% median error in functional connectivity estimates in a group-level comparison. We also discuss the implications of HRF variability for fMRI studies in the spinal cord. There is a need for more dialogue within the community on the HRF confound, and we hope that our article is a catalyst in the process.
Keywords
BOLD fMRI; HRF; resting state connectivity; aging; sex differences; confound
Subject
Biology and Life Sciences, Biophysics
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
