I am left-handed and suffer from depression and anxiety. Perhaps this is due in my case to the dominance of the right hemisphere, which processes more negative emotions, instead of the usual left side, which seems to process positive ones. As odd as it sounds, when I apply ice water to my right ear my symptoms are temporarily alleviated and I feel a positive mood lift.
Odd indeed, but if it works for you, that’s good. (How long does the effect last?)