The proposed study is aimed at developing a better understanding of factors involved in the development of executive function and self-regulation. Difficulties with self-regulation are an important factor in the development of psychopathology, and an understanding of the development of attentional mechanisms will allow researchers to better design interventions for children and adults who have difficulties associated with attention and self-regulation. The proposed study will first investigate the possibility that rules expressed in a context that provides information relevant to the instructed response will be easier to follow than rules that are expressed arbitrarily, or in a context that does not provide response relevant information. Second, it will identify which cognitive and neural processes are affected by the ways the rules are expressed. Specifically, we predict that expressing rules in a context relevant to the response reduces the amount of executive attentional resources needed to perform a subdominant, instructed response. A better understanding of these issues can be applied to design self-regulation training programs that can be used to help children and adults who have disorders related to difficulties with self-regulation. ? ?