The mask could be making her smarter. But the benefits won't be realized until she takes it off.

If carbon dioxide levels are made quite high quite often over a period of several weeks, the Carotids don't keep on closing back up. They stretch and accommo-date to become permanently broader, supply forever not only more oxygen to the brain but more nutrition and food energy and, most important, more cleansing away of toxins and fatigue poisons. https://web.archive.org/web/20190109044035/http://www.winwenger.com/ebooks/guaran3.htm