Aberrant levels of cortical myelin distinguish individuals with depressive disorders from healthy controls

Neuroimage Clin. 2021;32:102790. doi: 10.1016/j.nicl.2021.102790. Epub 2021 Aug 23.


The association between depressive disorders and measures reflecting myelin content is underexplored, despite growing evidence of associations with white matter tract integrity. We characterized the T1w/T2w ratio using the Glasser atlas in 39 UD and 47 HC participants (ages = 19-44, 75% female). A logistic elastic net regularized regression with nested cross-validation and a subsequent linear discriminant analysis conducted on held-out samples were used to select brain regions and classify patients vs. healthy controls (HC). True-label model performance was compared against permuted-label model performance. The T1w/T2w ratio distinguished patients from HC with 68% accuracy (p < 0.001; sensitivity = 63.8%, specificity = 71.5%). Brain regions contributing to this classification performance were located in the orbitofrontal cortex, anterior cingulate, extended visual, and auditory cortices, and showed statistically significant differences in the T1w/T2w ratio for patients vs. HC. As the T1w/T2w ratio is thought to characterize cortical myelin, patterns of cortical myelin in these regions may be a biomarker distinguishing individuals with depressive disorders from HC.

Keywords: Cortical myelin; Depression; Elastic net; LDA; MRI; Machine learning; T1w/T2w ratio.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Brain
  • Depressive Disorder*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Myelin Sheath
  • White Matter* / diagnostic imaging
  • Young Adult