Someone conducted a simple experiment to see if the facebook app was listening to their conversations. Spoiler: it's listening to your every word.

https://www.youtube.com/watch?v=U0SOxb_Lfps

Yeah, that's not a controlled experiment. I can think of at least three benign explanations that is consistent with not listening.

The experiment, the real, controlled (replicable!) one, isn't hard to do. You just need a couple of spare phones.

The patterns are there. But often the connection is meaningful, not causal.

https://en.m.wikipedia.org/wiki/Synchronicity

The pattern in this case is the connection between surreptitious listening and the suggestion.

The brain is still seeing a pattern though it is one of correlated meanings/abstractions, not concrete causes.