I just watched a TED talk about rats, joy, and why we need to put more focus in our lives on positive emotions.
I certainly see anticipatory behaviors in my ducks and geese. I personally, don't doubt that animals feel emotion.
I found the bit about how the rats seemed to prefer to "work" for their reward, vs just being given it, and I've read similar thoughts about how charity benefits the emotional health of the "giver", but actually harms the emotional health of the "receiver" (at least in most situations - emergency disaster relief could be an exception, but I know once that crisis stage is over, I would much prefer to assist in some way with the recovery of my community vs just passively accepting what others think I need. )
I can remember reading a comment from a tech giant claiming that once robots take over, everyone will have everything they need. I think that's publicity, rather than reality, myself. It may take away my joy of growing my own veggies and being surprised when some volunteer plant shows up. When I accomplish a sewing project, even if it was long and tedious, I am not convinced what I'm feeling is exactly "pride" , but rather happiness that I started something, stuck with it, and accomplished it.
So if permies are feeling a bit down from some of the horrible winter weather we're having, in may not be anti-depression herbs you need, but some pro-joy project, or activity, ideally involving other animals (that includes human animals.)