FREM3 and depressive symptom measurement: To further explore the potential involvement of the FREM3 gene in regulating depression-relevant neural and behavioral phenotypes, we identified rs1391187 as the SNP most strongly modulating FREM3 expression across both BA11 (p = 2.17 × 10−5, Figure 5E) and BA47 (p = 2.47 × 10−6, Figure 5F, Supplementary Table 2) in our postmortem cohort, and tested its effects (via proxy SNP rs1909022, R2 = 1.00, D′ = 1.00), on neural activity and perceptual processing speed in our in vivo cohort.