This has happened to me when an excruciatingly loud noise is heard, unexpectedly----or, when an extremely piercing, pain-inducing, bright light is seen. If I'm talking, it's like the OP said, I have a disconnect and start talking like a drunk person (slurring / stammering, etc.), and my mouth doesn't move the way I'm directing it----or, the way I WANT to direct it, is probably better-stated, and I forget what I'm saying.
It's sorta like..... If you could imagine that there's another you inside you (maybe, one could argue that it's "one's soul"), and when there's a bright light / loud sound, it's like that inside person falls-down (I actually feel like something drops-down inside of me----I guess it's that your blood pressure drops, like when you faint, except you don't faint), and I have to wait 'til they get-back on their feet, before I can function, again.
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White female; age 59; diagnosed Aspie.
I use caps for emphasis----I'm NOT angry or shouting. I use caps like others use italics, underline, or bold.
"What we know is a drop; what we don't know, is an ocean." (Sir Isaac Newton)