On the flavor structure of the light-quark sea distributions

The flavor structure of the nucleon sea provides unique information to test the statistical parton distributions approach, which imposes strong relations between quark and antiquarks. These properties for unpolarized and helicity distributions have been verified up to now by recent data. We will emphasize the properties of the light-quark sea and present here some new results which are a real challenge for forthcoming accurate experimental results, mainly in the high Bjorken-x region.