I'm also fortunate in that I have some brain MRIs of mine and in my opinion there is no marked reduction in white matter anywhere. I do not have the feeling that I'm suffering from permanent jet lag, though I must admit that I seldomly experience jet lag at all (which I guess could mean I have it all the time without noticing it somehow).
And here comes the most poignant bit of the article:
"It's interesting that there are individual differences, but we need
to understand what is causing them and find ways of creating environments
in which those differences can be attenuated," says Dirk-Jan Djik
which sounds horrible and ignorant. I don't want my differences to be attenuated. People are different, and for the most part that's a good thing. Being an owl is only a problem if it inhibits human function. Otherwise, I refuse to be labelled sick simply because I have a different innate sleep pattern. Being an owl works for me.