I notice that my heart jumps every time my phone rings.
It's usually a telemarketer, though, and my heart deflates as I decline the call.
But then it might be someone who I actually want to call me. It almost never is. But the chance exists, it has happened before, so the odds of my heart-jump being justified are non-zero, and somehow I appraise that over the imbalance of empirical data.
I don't know how many times Pavlov had to accompany the food with the bell to get the dogs to salivate, but I'm sure it was more than what I had with this thing.
Turns out that humans, too, are animals that can be conditioned. (I mean, it can't be just me, can it?)
RK