Subgenual cingulate connectivity as a treatment predictor during low-frequency right dorsolateral prefrontal rTMS: A concurrent TMS-fMRI study

Tan, Vinh; Jeyachandra, Jerrold; Ge, Ruiyang; Dickie, Erin W.; Gregory, Elizabeth; Vanderwal, Tamara; Vila‐Rodriguez, Fidel; Hawco, Colin

doi:10.1016/j.brs.2023.07.051

Cited by 5 publications

(1 citation statement)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Left DLPFC, bilateral insula, and precuneus connectivity maps were computed using the conventional seed-based approach. The 20 mm region of interest (ROI) in the left DLPFC was generated using the MNI coordinates from the rTMS treatment trial ( x = −38, y = 44, z = 26), 28 , 39 whereas both the bilateral insula and precuneus ROIs were selected using ROIs from the Glasser atlas ( Figure 1 ). 40 For each participant, each ROI average time-series was Pearson correlated to the time series of all other vertices, resulting in the seed connectivity map.…”

Section: Methodsmentioning

confidence: 99%

Effects of repetitive transcranial magnetic stimulation on individual variability of resting-state functional connectivity in major depressive disorder

Tan,

Downar,

Nestor

et al. 2024

jpn

Self Cite

View full text Add to dashboard Cite

Background: Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for major depressive disorder (MDD), but substantial heterogeneity in outcomes remains. We examined a potential mechanism of action of rTMS to normalize individual variability in resting-state functional connectivity (rs-fc) before and after a course of treatment. Methods: Variability in rs-fc was examined in healthy controls (baseline) and individuals with MDD (baseline and after 4–6 weeks of rTMS). Seed-based connectivity was calculated to 4 regions associated with MDD: left dorsolateral prefrontal cortex (DLPFC), right subgenual anterior cingulate cortex (sgACC), bilateral insula, and bilateral precuneus. Individual variability was quantified for each region by calculating the mean correlational distance of connectivity maps relative to the healthy controls; a higher variability score indicated a more atypical/idiosyncratic connectivity pattern. Results: We included data from 66 healthy controls and 252 individuals with MDD in our analyses. Patients with MDD did not show significant differences in baseline variability of rs-fc compared with controls. Treatment with rTMS increased rs-fc variability from the right sgACC and precuneus, but the increased variability was not associated with clinical outcomes. Interestingly, higher baseline variability of the right sgACC was significantly associated with less clinical improvement ( p = 0.037, uncorrected; did not survive false discovery rate correction). Limitations: The linear model was constructed separately for each region of interest. Conclusion: This was, to our knowledge, the first study to examine individual variability of rs-fc related to rTMS in individuals with MDD. In contrast to our hypotheses, we found that rTMS increased the individual variability of rs-fc. Our results suggest that individual variability of the right sgACC and bilateral precuneus connectivity may be a potential mechanism of rTMS.

show abstract

Section: Methodsmentioning

confidence: 99%