I rely mostly on DBT and CBT for my PTSD. It is helpful, along with Buddhist breathing and prayer. I do not take Klonopin any longer, as it exacerbates my depression.

That said, I have always believed that the eyes play a critical role in mood. Specifically, eye position. People who are depressed nearly always gaze downward. It occurred to me twenty years ago in one of my massive depressions that this might be an aggravating factor, rather than a sign/symptom. I started practicing elevating my gaze and, lo and behold, it does help me. No question on this at all.

So, personally, since the LGN and occipital cortices are hard-wired to areas of the brain involved with mood/affect,/memory, etc. the underlying concept in EMDR does, to me, maka a bit of sense. But I know very little about its ins and outs.