In this project we evaluate the way individuals solve conflicting situations in two separated cognitive areas, language and mathematic. Within the field of language, we focus on bilingualism. We are evaluating how speakers of more than one language manage the flow of activation across their languages. For instance, we are examining how to avoid the incorrect use of first language (L1) phonology (regularization into L1 of words in the second language). In the field of mathematical cognition, we are evaluating how children and adults resolve the coactivation of irrelevant information. For example, (a) when deciding the larger of these two numbers 46 52, the units are irrelevant and drive to an incorrect response (6 < 2); (b) when deciding that 2 + 4 = 8 is wrong, there is coactivation of the multiplication counterpart (2 x 4 = 8) which interferes in verifying the problem.