It’s a bit different for everyone
For me it’s stress or anxiety. Things I can normally handle (like some background noise for example) just make my brain not work when I’m stressed or anxious
Repeating sounds with the wrong periodicity. Some songs I cannot stand because the beat is a fraction too slow, making my brain go into “GET OVER WITH IT ALREADY” mode. It’s particularly grating with songs that have a “wwwWUB wwwWUB” thing that sounds like someone is turning the volume knob up and down.
A lot of things and it really depends on the day but something constant is repetitive noises while I am trying to sleep. When I was a kid someone snoring actually made me consider strangulation. I have slept in hotel bathtubs to escape it
For me it’s noise and light. I fucking hate summer people are outside everywhere the sun is blazing it’s so bright and noisy!!!
A noisy room full of people talking.
Yeah I get this one too. I can’t focus on any particular person, struggle to make out what someone sat next to me is saying, even if talking to me, and makes me very tired after a while.
Cluttered rooms.
I did not understand this about myself until after I married a person who is not comfortable until every surface is covered with stuff and every bit of wall perimeter is lined with piles of stuff.
same, my partner struggles to pick up after themselves and it gives me anxiety,
Clear sunny days and equivalently lit environments. Anything brighter than cloudy is too bright, it’s like all of that brightness fills my bandwidth and I can’t think properly.
Ambient heat above 25°C is another one, that feeling of bulgy, sweaty, tight, sticky meat suit does not help my composure. It’s acceptable in some very specific contexts, but VERY specific.
Crowds get my heart pumping as well, too many people to track, variable overload.
On the flipside, I’ve seen some comments mentioning clutter as being another potential trigger, but I’ve always found visual noise to be soothing. My brain enjoys picking out the details as a background process, and the more varied/colourful, the better! I still have my limits, though, like I have no problem with messiness, like clothes thrown about the place and tools/resources left on random surfaces, but trash is trash.
Busy visuals. I don’t mind a lot of sound and light. But if there is too much going on it is overwhelming. It could be a tray of glass falling, or the way too intense colors of a candy store
motorbikes are the worst
Someone talking to me, lecturing me