I've been working on a piece on improvement at bridge for this blog but while that comes together, here are some links you might enjoy.
Chess is a subject where the psychological issues have been explored in some detail. There is a lot of juicy material in the book Chess for Zebras by GM Jonathan Rowson.
While you wait to borrow/buy this book, you might like going through two interviews with the author that are more readily available here.
Around bridge improvement, Justin Lall wrote a thoughtful post here.
And back to the chess world, Phaedrus the great came up with a brilliant chart that translates almost bit by bit to bridge. One day I will try and make sense of this chart in a bridge context.