Agree. As posed in the OP the mice are exhibiting a fear response. What is, in my opinion, just about impossible to ascertain is if the mice “know they aren’t actually getting anywhere.”
From watching my mice, I’d say they do know they’re not getting anywhere. They really really like running in their wheel; occasionally it’s been left out the cage while cleaning by accident, or taken out at night when it rattles, and they’ll actually get up and have a run in the middle of the day, when they’d never normally be awake. Occasionally, when they had a very small wheel, they’d try and run virtually on top of each other, again something they’d never normally do.
The more I watch their behaviour, the more I think they’re not as stupid as they’re often thought to be. Well, except the one that regularly tried to climb in the wheel with the others, and run the other way… :smack: