The field diversified in the early 1990s when Simon Baron-Cohen and Uta Frith, building on the Wimmer and Perner study, and others merged it with research on the psychological and biological mechanisms underlying autism and schizophrenia. Concomitantly, Peter Fonagy and colleagues applied it to developmental psychopathology in the context of attachment relationships gone awry.[6] More recently, several child mental health researchers such as Arietta Slade,[7] John Grienenberger,[8] Alicia Lieberman,[9] Daniel Schechter,[10] and Susan Coates[11] have applied mentalization both to research on parenting and to clinical interventions with parents, infants, and young children.