Trauma triggers can cause subcortical reliving of past experiences, bypassing rational thought.

“When something happens in the present that is similar to what was dangerous or injured us in the past could be a violation, could be abandonment. It could be either an act of uh mistreatment or neglect. either when something in the present, you know this, of course, we don't remember trauma, we relive it. So the combat bit hears a car backfire and turns around like she's got a gun in her hand. She's not thinking, I'm walking down Main Street remembering combat. She's in combat. The the present goes away and it's subcortical lyic system amydala and you get flooded.”