I have a hunch, though, that often the problem is not emotional but actually physiological. If a ventilation system works well enough that air is not altogether too stale or humid or high in CO2, but not well enough to ensure the air is properly fresh, you could easily start feeling like there's something off, without being able to pinpoint exactly what's wrong. Most office ventilation systems have very few sensors and don't respond to changes in occupancy, or are otherwise hard to regulate, which can easily lead to air quality that is good-enough-but-not-quite-there and a desire to open a window. I've worked in offices that were stuffy all the time, but also in offices that were pleasant winter and summer, and nobody ever complained that the windows didn't open.

That can definitely be. We are absolutely dependent on air, so our air quality sensors are likely to be fairly sensitive.

Unless it's carbon monoxide poisoning...