Lou studies children's developing appreciation of mental states like belief, desire, and intention (their “theories of mind”). He is particularly interested in how advances in executive functioning (e.g., inhibitory control, working memory) affect the emergence and expression of early theories of mind. His current work also examines how developments in theory of mind and executive function influence the development of prospective memory and moral reasoning. Much of his research is conducted with preschool children, but he has also examined the early foundations of social cognition in infancy, the onset of constructivist theories of mind later in childhood, and the nature of theory of mind in individuals with autism. Lou also has a strong interest in methodological issues and the promotion of open science practices in psychological science.