The present paper explores the relevance that brain data have in constructing theories about the human mind. In the Cognitive Science era it was assumed that knowledge of the mind and the brain correspond to different levels of analysis. This independence among levels led to the epistemic argument that knowledge of the biological basis of cognition would not be relevant at a psychological level of explanation. Nowadays, however, modern neuroimaging technologies offer a powerful means to explore the cognitive functioning of the human brain. The authors argue that this technological revolution is associated with a new way of building theories of human cognition in which mind and brain are no longer independent nor autonomous. In contrast, the Cognitive Neuroscience era is marked by a continuous and bi-directional exchange of information between biology and cognition.