In a foreign language one can talk of subjects, one can unconcernedly use words, the uttering, the mention of which in one's native idiom would horribly embarrass.cf. The Foreign-Language Effect: Thinking in a Foreign Tongue Reduces Decision Biases (PDF) by Boaz Keysar, Sayuri L. Hayakawa, and Sun Gyu An
I look forward to reading Aneta Pavlenko's The Bilingual Mind, to be published by the Cambridge University Press next month.
Title of this post from here.