I tried rolling my eyes back last night, and my body started to get very uncomfortable after I did the relaxation technique.
It was almost painful, so 10 mins after it started, it still was going on, so I moved a little bit to stop it.
10 mins later, I was still rolling my eyes backwards, and I started snoring! I've never heard myself snore, and I brought myself back to full conciousness, and I never snore in sleep.
The eye trick seems to be working good!
I was also focusing on the breath coming in my nostrils, which kept me concentrated well.