What language do you dream in?
Michael Erard's essay in the NYTimes, "Dreaming in English," highlights that moment of language fluency in which dreamers begin dreaming in their learned tongue - as an escape from English?
As a native speaker, it isn't a profound event to dream in English, although I clearly remember the times when I started dreaming in French and in Chinese, both while studying abroad in the respective countries, and feeling excited about really "getting it." Then it became disturbing to me once I started mixing up the two or unable to think in the other foreign language when I was entrenched in the other. I don't recall ever actually speaking both in a dream, but often I do progress through languages: if I can't think of the word in Mandarin, I'll think of what it is in Cantonese. If the Cantonese word doesn't come to mind, I then think of it in French - and then in English. Worth a study? Maybe, maybe not. Is my brain mixed up? As I learn more - my most recent language being random Khmer phrases - perhaps the answer to that question will be...
oui / si / hai / jaa / shi / yes.