One theory is that your brain doesn’t want or need it. The intensity is such that it nopes out. Another is that the body is busy with physical survival, a bad car crash (sans TBI) being the classic scenario in which memory loss is common, and all resources are thus diverted.

Memory is not a video recorder. In addition, it’s a fickle bitch at times.

Emotion can enhance memory. You’ve clearly read that data. Emotion can also nudge memory into something inaccurate or distort the fuck out of memory, cognitive dissonance and personal biases being what they are. Worse, false memories are real.

Take a deep dive into the false memory data. It begins with Elizabeth Loftus back in the 90s and marches forward from there. How do you tell the difference between a false memory and a real memory? Short answer: you can’t. Sure, people and documentation around someone can prove a memory false but that won’t necessarily make the memory feel false to the person holding onto it.

Attention is a key component to encoding a memory in the first place. How focused is your attention if your car is airborne and you’re waiting for it to finish crashing? Maybe focused. Maybe not.

There are Masters Degrees in cognitive science devoted to memory studies and they still don’t have it figured out. But there’s plenty to read on the topic.