Can a ct / mri scan pick up depression, even if the depressive symptoms are temporarily not present in your life? i had this scan a few months ago and was fine but had recently been feeling severely depressed again?

Depression: I think that an MRI scan may pick up markers for depression if using a technique called intrinsic diffusivity encoding of arterial labeled spins. However, I am not sure that a conventional MRI would focus on this. I would not use the MRI to diagnose depression. REF: https://www.healthline.com/health-news/mri-detects-abnormalities-in-brain-depression#Welcome-to-the-connectome