Resting-state fMRI at 1.5T, 3T, and 7T: comparison of functional networks from data-driven Independent Component Analysis

Motivation: Resting-state BOLD fMRI reveals the brain's default functional state, with important insights for clinical applications and studying brain development. Few studies examined the impact of higher field strengths on detecting functional networks. Goal(s): To compare the reliability of resting-state BOLD fMRI at 1.5T, 3T, and 7T in identifying brain networks. Approach: Seven volunteers were scanned, and functional networks were extracted via Independent Component Analysis. Inter-subject similarity of the Default Mode and Visual Networks was used to assess reliability. Results: Higher field strengths improved inter-subject similarity, with 7T successfully detecting networks in all participants. Impact: This study compares resting-state BOLD-fMRI at 1.5T, 3T, and 7T, showing increased inter-subject similarity of brain networks at higher field strength. Only 7T reliably identified networks in all participants, suggesting greater reliability at ultra-high field strength.