BRIGhTMIND baseline analysis: functional connectivity correlates of cognitive impairment in treatment-resistant major depression

BRIGhTMIND was a randomised controlled trial comparing two types of transcranial magnetic stimulation (TMS) for treatment-resistant depression: standard repetitive TMS directed to the “F3” site (F3-rTMS) and connectivity-guided intermittent theta-burst stimulation (cgiTBS). In the trial, participants underwent clinical assessment, at which measures including the HDRS-17 observer-rated and PHQ-9 self-rated measures of depression, and the THINC-it battery of cognitive tests were obtained. They then had baseline brain imaging, which included 3-Tesla T1-weighted structural MRI and resting-state functional MRI. Within two weeks, they were randomised and began one of the two types of treatment, which lasted 20 sessions spanning across 4-6 weeks. The current protocol describes use of the baseline data from BRIGhTMIND to test specific hypotheses on the relationships between cognitive difficulties in MDD (measured with THINC-it) and brain activity (measured with resting-state functional magnetic resonance imaging, rsfMRI). It examines cognition and brain connectivity measured at baseline (prior to beginning TMS treatment). The findings of these analyses will guide future hypotheses around relationships between change in cognition and change in brain connectivity. For more information about the BRIGhTMIND trial, see: https://doi.org/10.1038/s44184-024-00077-8 (Briley et al., 2024); https://doi.org/10.1038/s41591-023-02764-z (Morriss et al., 2024)