Jake and I have four relatively unrelated and mildly-used degrees between the two of us (LET ME FLEX, I KNOW NO ONE CARES—but if you do, they're: Lit, Anth, Biomed, and CrimJust), and once in a while, one of us is ranting about a random topic inside another random topic, and the other does the slow confused-squint before realizing what's happening.
And what's happening is that we haven't gotten to stretch the brain parts of a certain area of study in a while and are going to run wild and circle everything back into that specific brainhole until it feels appreciated, no matter how unrelated. It's like a game: I say culture, he says globalized corporate crime, he says fascia, I say etymology of ISV, until one of us gives in and plays along.
This definitely led to some miscommunication in the first few years (it's been 12), but now it's fine, because a regular phrase in our house has become: I need ...to use...my degree! (But said in, like, a hyperventilating whine.)
Then the other person either asks questions or debates back because we're responsible academic antagonists like that, or else scrolls through their phone like I'm doing now and lets them lecture passively (this is the most acceptable defense mechanism against unwanted engagement, i.e. when the degree-user does not allow interaction, and we have both approved this method after extensive testing). Sometimes you don't need opinions, but talking to the rubber ducky, plants, pets, or the wall just doesn't do it. Sometimes you just need to stretch the brainhole while someone nods back, and this is actually the secret to marriage success.
(lol, JK we're not even married yet).