I was shocked when I dislocated my shoulder and they gave me IV Ketamine. I got that same experience, right there in the emergency room, sanctioned by the medical professionals.
It left a profound effect on me. Gave me a perspective about myself that I can't forget.
If it was legal and there was a safe way to do this again, I'd like to see how it's like when you're not in atrocious pain.
I had a similar experience during the beginning of a ketamine IV infusion that I was doing to see if I could treat central sensitization that I have: as I was disconnecting from feeling my body, I could visualize feelings in my body - literally seeing certain shapes. At one point a fear came to mind and then I could feel and experienced that fear-memory in a perfect sphere traveling down my body until it reached my root (root chakra, groin area) and presumably disappeared or dissipated, as did the actual feeling of fear contained in the sphere along with the memory associated with it.
Ketamine IV infusions are legal and paid for in Canada for pain, and it's legal for psychiatric diagnosis if referred by your doctor - however not covered by our health system. Arguably the health system, practitioners, and regulators don't know enough and so need to move forward slowly until there's time for proper research and guidance.
All other stimuli forming you dissipated, so then you were seeing a flat representation, or screen, a map of your body and then perceived the spot radiating pain as a multicoloured spot on the wall/screen? That's what I took from that description.
Maybe it has to be a combination of excruciating pain (endorphins) and ketamine.