Interesting! I'd also wonder if it has something to do with surrounding sensing. When you enter a room you briefly orient yourself and check for tigers hiding behind the window curtains, when remaining in the same room your mind is just checking diffs while entering a new room might cause the mind to throw away everything it had established and re-scan for danger. That'd be something I'd be curious to eliminate as a possible reason for the effect.
https://www.scientificamerican.com/article/why-walking-throu...