In the first part of this article, I discuss motivational variables in general, and interest in specific and propose that because of its biological roots, interest is a unique motivational variable. Furthermore, it is suggested that to demonstrate the uniqueness of interest, neuroscientific findings need to be considered. In the second section of the paper, I argue that the impact of the neuroscientific literature in the areas of social, educational and cognitive psychology has not been appropriately recognized. To support this claim, links between selected neuroscientific findings and motivational variables in general and interest in specific are discussed. Finally, some of the educationally relevant implications of interest research supported by neuroscientific findings are considered.