When I read this title, I thought the article would discuss the effects of self-centeredness in Chinese culture. But no, to my surprise, it found that the US participants displayed self-centeredness.
I have not lived in the U.S. and my experience of US culture has been through American friends and exported U.S. fare. So, I can't speak of any real experience of 'American culture.' However, having been raised by 'Chinese culture' influenced parents, and experienced my own sense of Chinese culture when I lived in Shanghai, China for 3.5 years not too long ago, in my experience, compared with 'Australian culture', 'Chinese culture' is far more self-centered.
The short of the long of it is that there was little or no concept of social nicety, and a high incidence of the 'look after your own and screw everyone else' / 'what's in it for me' mentality... which adds to the lack of social nicety. All exacerbated by the one-child policy which breeds countless overindulged insufferable princes and princesses... and I'm talking about children and adults.
The article also notes, "Nisbett adds that in some Asian cultures people use less blunt language, making it necessary for them to read between the lines, and imagine the perspective of the individual with whom they are speaking."
I believe that describes the infamous, "No means yes, and yes means no, and sometimes no and yes means maybe... and when I said apples, I really meant oranges... and you really should have been able to read my mind on that".
Article in New Scientist.