It's a fact that if you're the cause of the noise that you're less likely to cook off your startle reflex, the onset of fight flight when a sudden loud noise happens. When I'm in a good mood I sometimes sing and sing loudly just because. It's normal. Many people do it. theboy's been learning to sing and play "Rocking Robin", a go to standard in primary school when teaching the basics of music. It's also catchy as fuck and a total earworm.And if your startle reflex is up and someone unexpectedly starts singing "Rocking Robin" with the sudden noise perceived differently depending on where the burst occurs when sung it will get triggered. I had to remote myself behind a closed door.It's fucked you don't do it to yourself if you sing; it's unfair your ingrained habit doesn't afflict you but the exact same habit in someone else makes your brain prep for a defense response and floods you with adrenaline and dread.Exposure therapy in the long term for that is the way ahead for sudden noise but I am nowhere near that stage of treatment yet; it's just too fucking scary.That's how it is with a psychological injury; sudden bursts of song get you headed for a bunker.