 Along with Stanislawa Poplawska, a Polish neurobiologist, Leonova was the first woman to work in Constantin von Monakow's laboratory, which is now the Brain Research Institute of Zurich University.Leonova also researched at the Imperial University of Moscow's cutting-edge neurobiology laboratories, and in the United States.Her research began with studies of stillborn infants with congenital eye disease, discovering the connection between central nervous system damage and congenital eye disease.