A particularly interesting part that I did not expect from the title:
> Before the rats encountered the detour, the research team observed that their brains were already firing in patterns that seemed to "imagine" alternate unfamiliar mental routes while they slept. When the researchers compared these sleep patterns to the neural activity during the actual detour, some of them matched.
> “What was surprising was that the rats' brains were already prepared for this novel detour before they ever encountered it,”
Suppose we simplify the scenario and think of experiences as draws from a discrete probability distribution, e.g. p=[0.1, 0.1, 0.7, 0.1].
Suppose further that all events are a draw of type 1, 2, 3, or 4, and that our memory kept a count and updated the distribution - it is essentially a frequency distribution.
When we encounter a stimulus, we have to (1) recognize it and (2) assign a reward valence to it. If we only ever observed '3', the distribution would become very peaked. Correspondingly, this suggests that we would recognize '3' events faster and be better at assigning a reward valence to those events.
Then if we ever encounter a non-3 event, we would recognize it more slowly - it is well-established that recognition is tied to encounter frequency - and do a poorer job assigning reward valence to it. Together this means that we would do a bad job selecting the appropriate response.
Perhaps this scenario-based dreaming keeps us (and rats) primed so we're not flat-footed in new scenarios.
The question then becomes - if these scenarios are purely imagined, where are they being sampled from? If we never observe 1, 2, and 4...how do we know that these are the true list of alternative scenarios?
Yeah this part was pretty weird. How do they know that was caused due to the rats' brains firing because they were imagining unfamiliar routes, vs something completely unrelated to the maze routes at all? Just because the hippocampus flash patterns matched doesn't mean that's what the rats were thinking about while sleeping I'd think
> Before the rats encountered the detour, the research team observed that their brains were already firing in patterns that seemed to "imagine" alternate unfamiliar mental routes while they slept. When the researchers compared these sleep patterns to the neural activity during the actual detour, some of them matched.
> “What was surprising was that the rats' brains were already prepared for this novel detour before they ever encountered it,”