Lights are a common trigger, yes. But everyone is NOT triggered by the same things. Some people are triggered by music. Seizures often hit me as I am falling asleep & I do not wake afterward. I go to bed, am quiet for a couple of minutes & the seizure hits me. I have no memory of the event whatsoever. I am completely unaware, unless my bf tells me (in the morning) that I shook or gasped loudly & then became quiet again as we were falling asleep. That is me ~ my personal experience.

I am not familiar with astral projection.

You said that this was happening often, disturbing but also kind of cool. Personally, I really think that physical causes should be eliminated by professionals. If the experiences are psychological, then you can use that fact to help you deal with the events.

That is my personal advice.