The outlier to this the US Navy's experiments. Discussion on an older HN thread: https://news.ycombinator.com/item?id=19863319
I'm finding I can't really tell any difference in mood/alertness/whatever despite what my sensor thing reports. To the point that I don't know why I bother keeping this thing in the office.
My suspicion is these devices just can't really tell you much about how localized the readings are. And comparing a number for a large room to a converted closet is not at all meaningful.