Here is the final paragraph from a recent MRI paper by Farrow, Burgess, Wilkinson, and Hunter, “Neural correlates of self-deception and impression-management“:
Taken together, one appealing ‘pop-psychology’ interpretation of these results would be that being excessively honest with ourselves (‘faking bad’ at self-deception) is our least indulged in pursuit while giving out the best possible image of ourselves to other (‘faking good’ at impression-management) is a behaviour with which we are much more familiar and practised.
From the abstract you can read that “Our neuroimaging data suggest that manipulating self-deception and impression-management…engages a common network…”
Robin Hanson has suggested related hypotheses in the past. Caveat emptor, for the pointer I thank Michelle Dawson.