I thought it was dementia, but have only ever heard her from downstairs, never seen her actually do it, and it wasn't nice, especially as she fell over after moving away from the food bowl.
Ironically, I have been saying since last Dec that she wouldnt see this Christmas, but this past couple of weeks, as we have been getting closer, I have let myself think she would, but she has lost her balance quite a bit this morning, which could explain why she hasn't really moved for the past 2 hours. I would love to think it is something simple that could be treated, but deep down I dont really think it is.