When I was writing software for medical devices in the '90s, we had a very clear policies for dealing with cognitive drift that included performance ceilings, testing for drift in beta testing, etc. In our testing, 10 seconds was the absolute maximum time that a surgeon could "idle" and stay on task in surgery.

In addition, we found that including spinners, progress bars, etc. would not necessarily reduce the cognitive drift but would reduce emotional frustration.

The worst thing for frustration was UI elements being slow; buttons that responded slowly, scrolls that lag, pull-downs that didn't pull down. Exactly as this author notes. There was very little tolerance for those kinds of delays.

I presume that, like website response rate tolerance thresholds that have dropped from 5 seconds to less than 2 seconds now, the medical industry is probably using much lower times now.