"Combine antidepressants plus marijuana and its 66 cannabinoids and you've got a mystery stew for the brain ... Taking prescription antidepressants and simultaneously self-medicating with marijuana is not a good idea."
A car horn beeps and forces you to leave depression for that instant. The point of meditation is to continually work to expand that instant. Depression doesn't have to be terminal if you work continually on eliminating it.
(Provided by former Monk Jim Vuylsteke}
It's what's now called "neuroplasticity" i.e. you can remake your brain. One man had Alzheimer's and couldn't walk. But by focusing intensely on each trembling, modest step over time he's now able to sprint. He's maybe one in many millions, but he rewired neural circuits.