We all know that this season of American Horror Story is connected tangentially to season 1. In the 11th episode of Murder House, we learn that the Roanoke residents performed the first successful exorcism. Ryan Murphy has also given some cagey answers about a possible return of an antichrist child. Not only that, but they're in another haunted house.
Given that we know that Murphy eventually plans to link all the seasons, this analysis by HelloGiggles seems prescient. They point to a similar first shot of the seasons: With the camera moving through some trees to reveal a house. A similar shot took place during Coven, but it was just trees.
That suggests a couple things. First of all, that the show's obsession with place will continue. Second of all, given that the doctor at the end of the episode draws an analogy between a body and the foundation of a house, we can expect some subterranean element. Almost definitely that will be the linkage between the present time period and the past.
Third, we have the presence of trees. We all know trees grow up from the roots. Perhaps Murphy will suggest that there's a kind of natural horror lurking just beneath the surface of America. That would certainly explain the breathing ground.
One thing we know for sure: Ryan Murphy is not one for subtlety. So we'll know just how close this linkage is by season's end.