I wonder if the reason we find slow motion in movies interesting (e.g. makes things more salient) is related to the time-perception-slows-during-startles thing.

(Assuming the startle slow-down is a side effect of the brain kicking up retention, based on the current experience having valuable information, we might learn to implicitly associate side-effects like time dilation with "this is valuable experience information". But mostly I have no idea what I'm talking about; I'm not even sure it's a well-formed testable idea.)