Why do we sometimes wake up in a bad mood even after a good nights rest?

Question

And to expand on that: why is that bad mood so persistent?

In: Biology

Answer 1

There’s a few different possible ways:
Pathway explanation: We dreamed something that reactivated bad memories, or memories that made our mood turn sour – or woke some underlying anxiety. The usual coping strategies or avoidance techniques may not have been active in that dream state, so the mood is more persistent than usua, which feeds into the bad mood again.
Clearance model: the body may have rested, but the brains maintenance cycles are most effective in phase 3 or deep sleep. If those were to few, interrupted or not long enough, you might still feel awake, because the adenosine levels are just low enough in most brain regions to do so. But the brain regions that regulate mood and emotions may still need more maintenance, before they can bring your mood back to normal.