In a recent episode of The Psychology Podcast, Scott Barry Kaufman interviewed Joseph Goldstein. At 15:11 the question was asked about how Scott's psychological understanding of self seems to butt up somewhat against the Buddhist understanding (I'll try to link it at the discussion).
What Joseph said basically was that the same term was being used to describe slightly different things. That his understanding, which Scott agreed with, was that the psychological definition of self was a healthy balance of mind while the Buddhist understanding was more of an ontological description of the nature of the whole psycho-spiritual construct that constitutes our being.
My takeaway has been to think how these definitions might trip us up on the path. That we might mistake one for the other and intend to work towards Buddhist selflessness but in actuality be working towards psychological selflessness. For example, the Dalai Lama presumably has some deep level of realization of emptiness of self but seems to have a very healthy balance of mind. While someone else might be said to have a poor balance of mind (not a very strong sense of psychological self) but be totally taken over in the fundamental ignorance of Buddhist self.
Its kind of interesting and a challenge with words, how things can get lost or misinterpreted in translation and send us in the wrong direction.