This article shows that an Indian Tribe’s introduction of a policy along the lines of a Basic Income Guarantee reduced the incidence of mental illness in children.

E. Jane Costello, Scott N. Compton, Gordon Keeler, and Adrian Angold, “Relationships Between Poverty and Psychopathology: A Natural Experiment.JAMA: Journal of the American Medical Association. 2003: Volume 290, No. 15, pages 2023-2029.