Just had a visit with my mom, who has dementia. While I was there, she was talking and stopped all of a sudden and stared down. Her eyes then rolled to the left and she went totally limp. I checked to make sure she was breathing and she was. She then jerked out of that and her arms became rigid and she was shaking. That passed, and she got really pale. The resident nurse checked her blood pressure, which was normal. What could possible reasons be for this episode?