I was working in a nursing home that housed a retired Director of Nursing.  She had dementia and she thought she was at work.  She was always bossing the staff around and firing people. 

One day she had another resident visiting her in her room. I was right outside her door whenI overheard her saying "The staff around here is so slow...watch - I'll push this call light and we'll just see how long it takes someone to get here." 

I stood outside her door and counted 1,2,3, and then I poked my head in and said "Did you call?" She raised her eyebrows and looked at her friend and said "Now that one's pretty good."