Ketamine may act as a growth factor, facilitating changes in neural circuits related to mood and self-reflection, to provide relief for major depression.

“it's starting to raise what I consider a very exciting model of how ketamine could provide relief for depression which is that it's acting as a growth factor in the brain or at least it's mimicking the action of growth factors allowing the specific neural circuits that control things like mood outlook on the future self-reflection Etc allowing those circuits to change in ways that provide significant relief for major depression”