There isn't any citation to the (quite interesting) study finding mentioned as a premise in this article. My two older children are native speakers of BOTH Engl

There isn't any citation to the (quite interesting) study finding mentioned as a premise in this article. My two older children are native speakers of BOTH English and Modern Standard Chinese, and they once spoke to each other mostly in Chinese, although in recent years they have much more occasion to use English. There should have been follow-up studies on what happens to native multilingual persons when they suffer strokes by now, and there could even be brain-imaging studies on first-language and second-language multilingual persons by now, perhaps without conclusive results. This submission makes me curious about the author's premise than about his conclusion.