Some pointers here ... presentation-on-chess.
Not really useful pointers... I went through the first one, and all it said was that masters perform better in some spacial tasks (especially those with chess pieces), that any other benefit was inconclusive (and even if it was, it's a worthless test as regards education), and also that none of the tests on education were close to ideal, all but one of them being a choice between chess and do nothing (and of course some mental stimulation will trump nothing at all). It mainly comments on the limitations of the studies (despite their best efforts) and does not really lend them any credence whatsoever.
Are any of the others any "better"? (I think the first article was quite good, though - it was very statistically and methodologically sound).
Some pointers here ... presentation-on-chess.