The last sentence of the abstract does a good job of this:

>"Based on the present results, we propose that psilocybin with psychological support is a treatment approach that potentially revives emotional responsiveness in depression, enabling patients to reconnect with their emotions."

This hypothesis was borne out in the data produced by the experiment.

Essentially, they were able to increase empathy in their patients which enabled the patients to experience less isolation, thus relieving (some/most of) their depression.

Sounds like an alternative might then be loving kindness meditation which is basically a mental workout plan for opening up and feeling kindness to yourself, other people, and human experience in general.

They are comparing the effectiveness of SSRIs and psilocybin on depression by analyzing brain activity and the response to faces with different emotions (both agents work on serotonin receptors). Their conclusion is that while SSRIs lessens reaction to negative emotions, while psilocybin helps people think through their reactions. They conclude “Psilocybin represents a novel intervention for major depression that appears to be safe, rapid and potentially enduring in its antidepressant action.”

The abstract spells it out: "This suggests fundamental differences in these treatments’ therapeutic actions, with SSRIs mitigating negative emotions and psilocybin allowing patients to confront and work through them. Based on the present results, we propose that psilocybin with psychological support is a treatment approach that potentially revives emotional responsiveness in depression, enabling patients to reconnect with their emotions."