@Nimali - when your vision is overtaken by the 'overlay' of a non-reality (like...
It's interesting you used those metaphoric examples.
With the intrusive images like the burning building, it either slowly comes on and usually my anxious feelings toward it just speed up the process to the worst part, but sometimes they come suddenly and it almost reminds me of a flashback. Sometimes they're not as bad, but the way I think is in images, scenarios, all jam packed with senses(hearing, smell, taste, feeling,etc. So I can smell the ash, see the fire, feel the heat against my face, smell burning bodies, etc.) When they're not so bad, I can still remember where I am and what I was doing -- I'll just be put off for a second or two before returning back to what I was doing.
When it's worse, it's like I completely forget everything other than what I'm seeing. It's constant flashing images and that really disorients me.
The thing you mentioned that reminded me of something else.. I don't see this as a switch when I initially get the images. I wouldn't say it's an outside source that may be affecting me. I don't see it as some deity or other human that may have placed a microchip in my mind and activates at their own pleasure... (Though that would make a pretty interesting story and I feel bad for those who believe that. I'm terrified by what goes on in my own mind, I can't imagine the fear they may be experiencing.)
The only time I sort of think there's an outside force is when it feels like my mindset is sort of changing. I wouldn't say it's 100% outside source because the "outside source" I still consider a part of me. An example would be with the mindset. When my Past Self's mindset decides to be present in my mind, I feel like I can't control it and when it happens, it happens. I didn't instigate it nor can I prevent it, but I can see it happen against my will. But at the same time, my Past Self is still 'me' but just a different version of me.. sort of. Kind of like how people may act differently around their boss, but completely opposite around their love interest. Only difference is it feels like I can't predict when it'll fully take over.
When it feels like a switch.. would be when I'm experiencing very loud, disturbing intrusive thoughts. This only happens when I get overly stimulated whether it be intrusive thoughts, in a loud environment with other stimulus such as a crowd in a movie theatre, theme parks, construction areas, people yelling, etc., It's like my panic rises then once I hit that peak where I feel like I'm really going to lose it or when I realize I can't escape no matter what... that's when it feels like a switch just flipped. (I think it feels internally.) All of a sudden, my mind goes blank for a few minutes, I relax almost instantly, and when thoughts come back, it's like everything is fuzzy or blurry in my mind.. Sometimes if I get images, I still see the same ones that were just making me panic, but I feel so calm, it doesn't do anything. I become emotionless and eventually become distant. That's when I end up staring into space, bland face, usually have my arms wrapped around my knees close to my chest... it's just peaceful, but not a pleasant peaceful feeling if that makes sense. I couldn't control it but it happened.
I see this as sort of like, when my body experiences way too much stimulus, it shuts down to save itself and kind of goes into "hibernation."