As I've been discovering what I strongly suspect is adhd within my own brain (undiagnosed, and likely will never pursue such), I think my analogy is that my cpu is over clocked and running hot. Plenty of ram usually, and the storage is plentiful but in need of a defragging; but that CPU is always churning, even when there's no tasks assigned to it.

I'm also discovering that what I thought the H in adhd meant isn't what it really means in practice. I always thought of it is translating to a physical expression, but it doesn't, at least not for me. It's pretty much exclusively internal for me.