First of all, let me say that aging is not for the weak, or the ego challenged--it is damn difficult to look daily in the mirror and see the changes and feel the changes.
But after 40 years of marriage, I will tell you that something miraculous takes place. I see the man I married when I was 19, the age falls away, but the intimacy of 40 years stays sharply in the foreground. It is a wonderful thing to be seen by your spouse as that young girl he married.
So I would say there is more of an increase in the romantic mind due to the shared years and experiences we bring to the relationship.