lose the thread
To stop understanding or following something, such as an explanation, because one has become distracted or confused. Sorry, can you back up? I lost the thread when you started talking about genes. I think this writer is trying to intentionally make us lose the thread so that the story becomes disorienting.
lose the thread
Cease to follow the sense of what is said. For example, It was such a long story that I soon lost the thread. This expression uses thread in the sense of "something that connects the various points of a narrative." [Mid-1900s]
lose the (or your) thread
be unable to follow what someone is saying or remember what you are going to say next.