Byron Richards recommends pantethine for brain fog. It works great, but for some people can be stimulating as well. Hubby got into a brain fog patch and could take 300 mg in the morning, but none the rest of the day or he wouldn't sleep. And regarding sleep, I've been shocked to find out how much magnesium citrate it takes for me to sleep well. I've settled on 300 mg in the morning and 900 mg at night. And if I don't get hungry or thirsty during the night, I sleep pretty darn well these days.