Barbara Landau is a cognitive scientist who works on the representation of space and language and the mapping between the two systems. She has carried out work on normally developing children and normal adults, as well as children and adults with neurological impairment, including people with Williams syndrome. Before coming to Johns Hopkins University in 2001, she held faculty positions at Columbia University, University of California-Irvine, and the University of Delaware. In 2009, she was named a fellow of the John Simon Guggenheim Foundation and the American Academy of Arts and Sciences. She is also a fellow of the American Association for the Advancement of Science, the Cognitive Science Society, the Association for Psychological Science, and the American Psychological Association. James E. Hoffman is a Professor at the University of Delaware. He works on visual representation, especially the nature of attentional mechanisms in the brain, using traditional experimental methods as well as event-related potentials in the brain to measure attention. He is a fellow of the Association for Psychological Science.