I may have ADHD, I never went for a diagnosis and found body doubling useful at times, especially when I was in school some decades ago, back then I had no name for it. However, I find white noise very helpful with staying on the task and with increased focus. My company moved, about a year ago, into a very cramped office that is also extremely noisy. This exasperated me, I would get drained of energy in a couple of…
Whenever I'm switching between tasks (thinking vs reading vs writing) I'd either turn the sound off or on, given I needed more or less attention at the moment. Minor problem with that was that sometimes unexpectedly I'd stick with the new task longer than expected, start to get bored, but w/e background sound I had on didn't match the task, so I'd look for something else... Overall a bit annoying for some groups of tasks.
I'm experimenting with mixing music with podcasts with extra noise and turning it on and off, but I also made https://stimulantnoi.se/ (with extra reading on psychological basis of the design and link to open source standalone desktop app on https://incentiveassemblage.substack.com/p/why-is-nobody-ser...). It allows for mixing (including uploading additional) sounds into sets and binds switching between those whole sets to media keys for quick access.