Researchers from the Saban Research Institute of Children’s Hospital Los Angeles (CHLA) found structural differences in the cerebral cortex of patients with depression when examining brain MRI.

The study, published in Molecular Psychiatry and led by Ravi Bansal, PhD, and Bradley S. Peterson, MD, is the first to provide in vivo evidence for the presence of anatomical neuroplasticity in the human brain.

Researchers acquired anatomical MRI scans before testing and again at the end of a 10-week study period for 41 patients with chronic depression, while 39 healthy volunteers were scanned once. Active medication duloxetine, a selective serotonin and norepinephrine reuptake inhibitor, or placebo were given to the patients at random.

“Our findings suggest that thickening of the cerebral cortex is a compensatory, neuroplastic response that helps to reduce the severity of depressive symptoms,” said Peterson, director of the Institute of the Developing Mind at CHLA, in a statement. “Patients off medication have a thickened cortex, and the thicker it is, the fewer the symptoms they have. Treatment with medication then reduces the severity of symptoms, which in turn reduces the need for biological compensation in the brain—so that their cortex becomes thinner, reaching thickness values similar to those in healthy volunteers.”

Researchers note that although this particular study was conducted on adults, pairing a randomized controlled trial with MRI scanning can be applied to various other populations.