Attention lapses due to sleep deprivation due to flushing fluid from brain

Could ADHD be caused by a broken flushing response? Lots of flushing followed by intense focus caused by the tabula rasa?

I'm not an expert, but that wouldn't really fit with my understanding of ADHD. It's not that we have a lack of attention ("defecit" of attention, as the name suggests), it's an impaired ability to direct it.

To abuse a metaphor, the sleep-deprivation-induced spontaneous CSF flush is slamming on the brakes of a car, and ADHD related attention shifts would be more like a drunk toddler is turning the steering wheel wherever they please, but the gas/brakes still work fine.

I suppose it's possible, but it seems less likely to me because ADHD is a life long neurodevelopmental disorder that shows [visible physical changes in the brain on scans](https://pmc.ncbi.nlm.nih.gov/articles/PMC7879851/). That said, there are statistically more people with narcolepsy who have ADHD, and the same goes for sleep apnea. There's a number of hypotheses I've read as to why, to name a couple: related epigenetic causes, or [possible misdiagnosis](https://pmc.ncbi.nlm.nih.gov/articles/PMC7336577/) (narcolepsy is much harder to diagnose than ADHD if you don't have textbook symptoms). So there is definitely something there.

Disordered sleep can cause executive dysfunction similar to ADHD, but it does not cause ADHD. It certainly can exacerbate it or be diagnosed incorrectly.

Not sure if it's related, but I have way more ADHD-like symptoms if I'm on late sleep schedule, but sleeping the same amount of hours.

Even if this is a possible factor it most certainly would not be the only cause.