Giving psilocybin, the psychedelic in magic mushrooms, to rats made them more optimistic in the longer term, suggesting that the psychedelic substance could have great potential in treating a core symptom of depression in humans.

[u/mvea]

https://newatlas.com/medical/psilocybin-optimism-depression/

[u/Chronotaru]

I think one of the most important aspects of psilocybin is for the majority of people it leaves you feeling with your emotions and sense of humanity restored. SSRIs may help a minority of people with their depression but their method of action for too many is emotional numbing and loss of self. You cannot get better by having something take away things from you as a person.