Little brown mouse Harriet was having a bad day.
She and her mother, Pudd'n, have been having seizure-like fits. In Harriet's case she simply shuts down and goes into her own little world, looking as if she is depressed and forlorn. The times I have found her like this I scoop her up in my hand and cuddle her until she perks up. When she does perk up she usually demands a treat. And then she is all happy and wanting to play, running up and down my arms.
Addendum: While holding little Harriet Trish came up to pet her. Trish walked across the room to us had band built up an electro-static charge. Trish reached down to rub her finger tip between Harriet's ears when *SNAP*JOLT*EEEEEEK!* Little Harriet let out a pathetic yelp and sat right up, cleaning the spot where the offending spark had made contact with her. Harriet seemed to literally come back to life after her little electrocution.